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Mesh-supported V2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

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Tungsten 2025年第1期 100-111页

作者： Zhi-Qi Zhang liu Yang Wen Luo Vladimir An Jing Li bao-Dan liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient V2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and V2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based V2O5-WO3/TiO2catalysts,our V2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the V2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny V2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

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RESEARCH ON THE FLOW PROPERTY IN THREE DIMENSIONAL CAVITY OF MICRO-CHANNEL

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Journal of Hydrodynamics 2006年第1期18卷 20-25页

作者： bao Fu-bing lin Jian-zhong liu Yan-hua Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China China Jiliang University Hangzhou 310018 China

The vortical property in a three dimensional cavity of micro-channel flow, which is very important, was investigated numerically. The results show that the rotation direction of vortex in the cavity depends on the dimension and shape of the cavity as well as the viscosity of the fluid. With the dimension and shape of the cavity fixed, there exists a critical inlet velocity. When the inlet velocity is less than the critical value, the rotation direction of vortex in the cavity will change. The critical velocity is directly proportional to the vis- cosity of the fluid, and inversely proportional to square of the thickness, length and depth of cavity. For the ratio of length and depth of cavity equals to one, there is a critical dimensionless parameter Recr , when Recr＇ is less than Recr＇ , the rotation direction of vortex will change too. Recr＇ is equal to 11.8 approximately.

关键词： micro channel cavity flow vortex numerical simulation

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

Determination of Quality Properties of Soy Sauce by Support Vector Regression Coupled with SW-NIR Spectroscopy

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Chemical Research in Chinese Universities 2011年第3期27卷 385-391页

作者： liu Tong bao Chun-fang REN Yu-lin College of Chemistry Jilin UniversityChangchun 130021P.R.China Harbin Centre for Disease Control and Prevention Harbin 150056P.R.China

The modern near-infrared(NIR) spectroscopy analysis is a simple, efficient and nondestructive technique, which has been used in chemical analysis in diverse fields. Shortwave NIR spectroscopy is also a rapid, flexible, and cost-effective method to control product quality in food industry. The method of support vector regression coupled with shortwave NIR spectroscopy was explored for the nondestructive quantitative analysis of the important quality parameters of soy sauce, including amino nitrogen content, total acid content, salt content and color ratio. In this study, the support vector regression(SVR) models based on subtractive spectra and positive spectra were found and compared, the results show that the subtractive spectrum was more excellent than the positive spectrum. Meanwhile, R and RSE were determined, respectively, by means of original spectra and pretreated spectra[standard normal variate (SNV), first-derivative and second-derivative], and the corresponding models were successfully established. The best prediction was achieved by a support vector regression model of the first derivative transformed dataset. In addition, the result obtained by the proposed method was compared with that of Partial Least Squares(PLS), which showed that the generalization performance of the classifier based on SVR was much better than that of PLS. The results demonstrate that shortwave NIR spectroscopy combined with SVR is promising for the quality control of soy sauce.

关键词： Shortwave near-infrared spectroscopy Support vector regression Processing Soy sauce

基于自适应续流比的混合式步进电机转矩脉动抑制方法

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陕西科技大学学报 2025年第1期43卷 142-151,202页

作者：王焜刘宝泉刘艺张浩铭刘俊陕西科技大学电气与控制工程学院陕西西安710021 西安西电高压开关有限责任公司陕西西安710018

混合式步进电机细分驱动存在较大的电流纹波,导致转矩脉动明显.通过分析H桥驱动电路的续流过程,提出一种基于自适应续流比的混合式步进电机转矩脉动抑制方法.该方法利用环型分配器产生的细分指令电流i ref与实际电流i相比较,以区分当前... 详细信息

混合式步进电机细分驱动存在较大的电流纹波,导致转矩脉动明显.通过分析H桥驱动电路的续流过程,提出一种基于自适应续流比的混合式步进电机转矩脉动抑制方法.该方法利用环型分配器产生的细分指令电流i ref与实际电流i相比较,以区分当前时刻所需的续流模式.在快速续流模式下,实时监测电流指令与实际电流的差值Δi ref,通过自适应系数k动态调节续流时间,直至电机相电流快速下降至给定电流i ref后切换至缓慢续流模式.对续流时长与快速续流占总续流时间的比例自适应调节以适应不同工况下步进电机的平稳运行,有效降低了转矩脉动.最后,搭建MATLAB/Simulink仿真平台并进行实验验证,结果表明,与传统混合续流控制相比,所提方法能够有效减小步进电机的转矩脉动.

关键词：混合式步进电机自适应续流比电流纹波转矩脉动

Palladium-catalyzed enantioselective carbonylation reactions

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Science China Chemistry 2022年第3期65卷 441-461页

作者： Jin-bao Peng Xin-Lian liu lin Li Xiao-Feng Wu School of Biotechnology and Health Sciences Wuyi UniversityJiangmen 529020China Dalian National Laboratory for Clean Energy Dalian Institute of Chemical PhysicsChinese Academy of SciencesLiaoning 116023China Leibniz-Institut für Katalyse e.V. Albert-Einstein-Straße 29aRostock 18059Germany

Carbonylation,one of the most powerful approaches to the preparation of carbonylated compounds,has received significant attention from researchers active in various ***,impressive progress has been made on this subject over the past few *** the various types of carbonylation reactions,asymmetric carbonylation is a straightforward methodology for constructing chiral *** rhodium-catalyzed enantioselective hydroformylations have been discussed in several elegant reviews,a general review on palladium-catalyzed asymmetric carbonylations is still *** this review,we summarize and discuss recent achievements in palladium-catalyzed asymmetric carbonylation ***,this review’s contents are categorized by reaction type.

关键词： palladium catalyst enantioselective carbonylation chiral

Engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong liu College of Chemistry and Materials Engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Atomic economy Radical pathway regulation Rubidium atom coordination Biomass valorization

Effects of Nb on the microstructure and mechanical properties of 38MnB5 steel

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International Journal of Minerals,Metallurgy and Materials 2018年第10期25卷 1181-1190页

作者： Li lin bao-shun Li Guo-ming Zhu Yong-lin Kang Ren-dong liu School of Material Science and Engineering University of Science and Technology BeijingBeijing 100083China Ansteel Technology Center Anshan 114009China

The effects of the microalloying element niobium(Nb) on the microstructure and mechanical properties of the hot stamped steel 38 Mn B5 were investigated. The impact of Nb addition on the microstructure was studied through scanning electron microscopy(SEM), transmission electron microscopy(TEM), and X-ray diffraction(XRD). The experimental results indicated that the microstructures of the steel containing Nb were finer than those of the steel without Nb. Moreover, Nb mainly presented as a second-phase particle in 38MnB5 steel, and the particles included Nb carbonitrides. In addition, the tensile strength and elongation of the hot rolled and hot stamped steels were also measured, and they demonstrated that the appropriate addition of Nb was beneficial to the mechanical properties of 38 MnB5. Under the same conditions, the tensile strength of 38 MnB5 Nb was higher than that of 38 MnB5, which increased from 2011 to 2179 MPa. The yield strength also increased from 1316 to 1476 MPa, and the elongation increased from 5.92% to 6.64%. Overall, Nb had a positive effect on the performance of the hot stamped steel.

关键词： hot stamping steel CCT curve microstructure mechanical properties precipitation

Modelling the Effects of Pest Control with Development of Pesticide Resistance

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Acta Mathematicae Applicatae Sinica 2021年第1期37卷 109-125页

作者： Bing liu bao-lin KANG Feng-mei TAO Gang HU College of Mathematics and Information Science Anshan Normal UniversityAnshan 114007China

In this paper,we assume that the pest population is divided into susceptible pests and infected pests,and only susceptible pests do harm to *** the two methods of spraying pesticides and releasing infected pests and natural enemies to control susceptible pests(the former is applied more frequently),and assuming that only susceptible pests develop resistance to pesticides,a pest control model with resistance development is *** using the basic theory of impulsive differential systems and analytical methods,the sufficient condition for the global attractiveness of the susceptible pest eradication periodic solution is *** with numerical simulations,the effects of spraying frequency of pesticides on critical threshold conditions for eradicating susceptible pests are *** results confirm that it is not that the more frequently the pesticides are sprayed,the better the result of the pest control *** control strategies for eradicating susceptible pests are proposed:switching pesticides and releasing natural enemies ***,the parameters in the critical threshold are analyzed from the following two aspects:(1)The key factors affecting pest control are determined by parameter sensitivity *** results indicate that the correlation of the critical threshold concerning the killing efficiency rate and the decay rate of pesticides to susceptible pests varies due to the resistance development of susceptible pests.(2)Three-dimensional graphs and contours of susceptible pest eradication critical threshold with two parameters are simulated,and the effects of the main parameters on the critical threshold are analyzed.

关键词： pest control model resistance pesticide function susceptible pest eradication periodic solution