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Stability of Cu-Mn bimetal catalysts based on different zeolites for NO_x removal from diesel engine exhaust

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Chinese Journal of Catalysis 2018年第4期39卷 800-809页

作者： Shuang Zhao Liming Huang boqiong jiang Min Cheng Jiawei Zhang Yijing Hu School of Environmental Science and Engineering Zhejiang Gongshang UniversityHangzhou 310018ZhejiangChina

Cu–Mn bimetal catalysts were prepared to remove nitrogen oxides(NOx)from diesel engine exhaust at low *** a Cu/Mn ratio of 3:2,the NOx conversions at 200°C reached 65%and 90%on Cu–Mn/ZSM‐5 and Cu–Mn/SAPO‐34,*** a hydrothermal treatment and reaction in the presence of C3H6,the activity of Cu–Mn/SAPO‐34 was more stable than that of Cu–Mn/ZSM‐*** obvious variations in the crystal structure or dealumination were observed,whereas the physical structure was best maintained in Cu–Mn/SAPO‐*** atomic concentration of Cu on the surface of Cu–Mn/SAPO‐34 was quite stable,and the consumption of octahedrally coordinated Cu2+could be ***,the proportion of octahedrally coordinated Cu2+on the surface of Cu–Mn/ZSM‐5 significantly ***,besides the structure,the redox cycle between Cu+and octahedrally coordinated Cu2+played an important role in the stability of the catalysts.

关键词： Cu-Mn/SAPO-34 Cu-Mn/ZSM-5 Diesel engine exhaust Hydrothermal stability Resistance to hydrocarbons

理论带动实践，知识提高能力——环境工程“十三五”优势专业的核心骨干课程建设研究

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科教文汇 2020年第2期 70-71页

作者：江博琼浙江工商大学环境科学与工程学院

为建设具有浙江工商大学特色的环境工程“十三五”优势专业,通过优化学分分布、理论结合实践、科研结合教学,进行专业核心骨干课程建设,提升学生对知识的全面掌握程度,增强学生工程实践能力和创新能力,为培养具有经济管理能力的工程人... 详细信息

为建设具有浙江工商大学特色的环境工程“十三五”优势专业,通过优化学分分布、理论结合实践、科研结合教学,进行专业核心骨干课程建设,提升学生对知识的全面掌握程度,增强学生工程实践能力和创新能力,为培养具有经济管理能力的工程人才和具有创新能力的相应领域浙商提供良好的平台。

关键词：核心骨干课程建设学分优化工程能力

Heat Transfer and Friction Characteristics of Printed Circuit Heat Exchangers with Different Channel Structures for S-CO_(2) Power System

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Journal of Thermal Science 2024年第3期33卷 1132-1147页

作者： jiang Tao LI Mingjia Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

Printed circuit heat exchanger(PCHE)has been widely used in supercritical carbon dioxide(S-CO_(2))power systems because of its high heat transfer efficiency and good ***,due to the large variety of PCHE configurations,channel selection in practical applications lacks a ***,this paper discussed the heat transfer and friction characteristics and the synergy of three fields in the channel under the guidance of the field synergy principle for four typical PCHE ***,the comprehensive performance of four channels was ***,the heat transfer and friction factor correlations for S-CO_(2)in four channels were *** findings demonstrate that the synergy of velocity and pressure fields of the straight channel PCHE is better(β≈180°),so its resistance loss is relatively *** zigzag and sinusoidal wavy channels and the airfoil fins can reduce the angle a between the temperature gradient and velocity,thus enhancing the heat *** sinusoidal wavy channel can reduce flow resistance compared to the zigzag channel due to the rounded *** streamlined airfoil structure can guide the flow and reduce backflow,thus reducing resistance *** the range of Re studied in this paper,the maximum error of the proposed heat transfer and friction factor correlations of PCHE is 7.0%,which shows good fitting *** research in this paper can provide a reference for the selection and design of PCHE with different channel configurations.

关键词： printed circuit heat exchanger supercritical carbon dioxide typical channel structure field synergy analysis

An improved initial rotor position estimation method using high-frequency pulsating voltage injection for PMSM

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Defence Technology（防务技术） 2024年第3期33卷 19-29页

作者： Yang jiang Ming Cheng School of Electrical Engineering Southeast UniversityNanjing 210096China

High frequency pulsating voltage injection method is a good candidate for detecting the initial rotor position of permanent magnet synchronous ***,traditional methods require a large number of filters,which leads to the deterioration of system stability and dynamic *** order to solve these problems,a new signal demodulation method is proposed in this *** proposed new method can directly obtain the amplitude of high-frequency current,thus eliminating the use of filters,improving system stability and dynamic performance and saving the work of adjusting filter *** addition,a new magnetic polarity detection method is proposed,which is robust to current measurement ***,experiments verify the effectiveness of the method.

关键词： Initial position detection Signal demodulation algorithm Magnetic polarity detection Filter elimination

Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery

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Carbon Energy 2024年第7期6卷 14-25页

作者： Leijun Ye Weiheng Chen Zhong-Jie jiang Zhongqing jiang Key Laboratory of Optical Field Manipulation of Zhejiang Province Department of PhysicsZhejiang Sci-Tech UniversityHangzhouChina Department of Mechanical Engineering Ningbo University of TechnologyNingboChina Guangzhou Key Laboratory for Surface Chemistry of Energy Materials Guangdong Engineering and Technology Research Center for Surface Chemistry of Energy MaterialsCollege of Environment and EnergySouth China University of TechnologyGuangzhouChina

Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma *** a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V *** hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported ***,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling ***-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics *** work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs.

关键词： heterojunction oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes

Hybrid rogue waves and breather solutions on the double-periodic background for the Kundu-DNLS equation

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Communications in Theoretical Physics 2024年第5期76卷 33-48页

作者： DongZhu jiang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 01022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,by using the Darboux transformation(DT)method and the Taylor expansion method,a new nth-order determinant of the hybrid rogue waves and breathers solution on the double-periodic background of the Kundu-DNLS equation is constructed when n is *** and rogue waves can be obtained from this determinant,*** to this,the hybrid rogue waves and breathers solutions on the different periodic backgrounds are given explicitly,including the single-periodic background,the double-periodic background and the plane wave background by selecting different *** addition,the form of the obtained solutions is summarized.

关键词： double-periodic background hybrid rogue waves and breather darboux transformation Kundu-DNLS equation

A newly unraveled 13.6-year oscillation from GPS displacements and its potential implications for the dynamic reference frame

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Science China Earth Sciences 2024年第10期67卷 3204-3212页

作者： Hao DING Weiping jiang School of Geodesy and Geomatics Hubei Luojia LaboratoryWuhan UniversityWuhan 430079China GNSS Research Center Wuhan UniversityWuhan 430079China

Numerous practical geodetic and geophysical applications necessitate precise measurements of GNSS displacements at the millimeter or sub-millimeter level. To attain such precision, it is imperative to identify and analyze the unidentified decadal signals inherent in the GPS displacements. In this research, we employ the optimal sequence estimation method to effectively detect an about 13.6-year oscillational signal with an excited amplitude of 3.6±1.2 mm in the U-components of the GPS displacements. It is noteworthy that this signal demonstrates a consistent spatial pattern characterized by the spherical harmonic Y_(2,-2). We conduct a comparative analysis with the 13.6-year oscillation observed in length-of-day variations(and geomagnetic records), finding that they are in reverse phase. After eliminating the Earth's external excitation sources through the utilization of two distinct in-situ hydrological records, we suggest that the 13.6-year GPS signal may come from the internal motions within the Earth. However, the specific excitation source and the detailed physical mechanism remain uncertain. Additionally, we develop a mathematical displacement model to explain the 13.6-year signal. Our findings indicate that this signal can result in displacements of up to 1.37 mm and velocity effects of 0.63 mm/yr(for U-component) at maximum. These results underscore the necessity of incorporating this 13.6-year signal into the construction and maintenance of a dynamic reference frame at the millimeter level.

关键词： GPS displacements Decadal changes 13.6-year oscillation Displacement model Dynamic reference frame

Capturing Plateau-Rayleigh instability in silver nanowires via ultrafast electron microscopy

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Nano Research 2024年第9期17卷 8402-8407页

作者： Shuai jiang Volkan Ortalan Department of Materials Science and Engineering University of ConnecticutStorrsCT 06269USA

Understanding the structural stability of nanomaterials such as nanowires is imperative for their practical ***,using single-shot ultrafast transmission electron microscopy,we captured the Plateau-Rayleigh instability behavior of silver nanowires decomposing into silver nanoparticles upon laser irradiation on nanosecond time *** found that this dynamic process can be accelerated by a factor of 10 through increasing the peak laser fluence from 6.03 to 14.60 mJ/cm^(2).Moreover,by comparing the laser fluence required to initiate the Plateau-Rayleigh instability in silver nanowires on carbon and Formvar membranes,it was found that the main driving force for the Plateau-Rayleigh instability in this study was substrate *** element analysis and molecular dynamics simulations are also applied to estimate the temperature jump of the nanowires and atomistic behavior,*** addition,the complex motions of silver nanowires under laser irradiation were systematically investigated by combining the results of ultrafast transmission electron microscopy with scanning electron microscopy characterizations and were determined to be related to nanowire-membrane interactions or pre-existing stresses on the nanowires,which in turn demonstrated the potential of ultrafast transmission electron microscopy for the characterization of nanomaterials and devices under extreme conditions.

关键词： silver nanowire Plateau-Rayleigh instability ultrafast transmission electron microscopy molecular dynamics simulation

Mo2B2O2 MBene for Efficient Electrochemical CO Reduction to C2 Chemicals: Computational Exploration

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 342-350页

作者： Zhang, Bikun jiang, Jianwen Natl Univ Singapore Dept Chem & Biomol Engn Singapore 117576 Singapore

Emerging as a new class of two-dimensional materials with atomically thin layers, MBenes have great potential for many important applications such as energy storage and electrocatalysis. Toward mitigating carbon footprint, there has been increasing interest in CO2/CO conversion on MBenes, but mostly focused on C-1 products. C2+ chemicals generally possess higher energy densities and wider applications than C1 counterparts. However, C-C coupling is technically challenging because of high energy requirement and currently few catalysts are suited for this process. Here, we explore electrochemical CO reduction reaction to C-2 chemicals on Mo2B2O2 MBene via density-functional theory calculations. Remarkably, the most favorable CO-COH coupling is revealed to be a spontaneous and barrierless process, making Mo2B2O2 an efficient catalyst for C-C coupling. Among C-1 and C-2 chemicals, ethanol is predicted to be the primary product. Furthermore, by charge and bond analysis, it is unraveled that there exist significantly more unbonded electrons in the C atom of intermediate *COH than other C-1 intermediates, which is responsible for the facile C-C coupling. From an atomic scale, this work provides microscopic insight into C-C coupling process and suggests Mo2B2O2 a promising catalyst for electrochemical CO reduction to C-2 chemicals.

关键词： C-2 chemicals C-C coupling density-functional theory MBene Mo2B2O2 GENERALIZED GRADIENT APPROXIMATION CARBON-MONOXIDE ELECTROREDUCTION CONVERSION CATALYSTS INSIGHTS DESIGN SELECTIVITY EXCHANGE