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Journal of Natural Gas Chemistry 2009年第4期18卷 415-420页

作者： Yile li xiaoyu Zhang Enyan Long Hongmei li Dongdong Wu li Cai Maochu Gong Yaoqiang Chen Key Laboratory of Green Chemistry ＆ Technology of the Ministry of Education College of Chemistry Sichuan University Chengdu 610064 Sichuan China

Pd/YZ-Al2O3 （Y and Zr modified Al2O3, and hereafter, labelled as A1） catalysts with 4 wt% additive CeO2 and/or La2O3 were prepared and characterized by X-ray photoelectron spectroscopy （XPS）, NO-temperature programmed desorption （NO-TPD）, Nz-adsorption/desorption （Branauer-Emmet-Teller BET method）, X-ray diffraction （XRD） and CO-chemisorption. Catalytic activities for CH4, CO and NO conversion were tested in a gas mixture simulated the emissions from natural gas vehicles （NGVs） operated under stoichiometric conditions. The results indicated that all catalysts exhibited excellent catalytic performances for CH4 and CO oxidation and the promoting effect of CeO2 or La2O3 was significant for NO conversion. XPS results showed that the electron density around Pd was increased by CeO2 and/or La2O3, the binding energy of Pd 3d decreased as the order： Pd/Al 〉 Pd/Ce/Al 〉 Pd/La/Al 〉 Pd/CeLa/Al. The electron-rich Pd showed Rh-like catalytic properties which exhibited good activity for the reduction of NO. NO-TPD results showed that the addition of CeO2 and/or La2O3 increased NO adsorption on surface, and promoted the conversion of NO.

关键词： NGVs under stoichiometric condition palladium catalyst XPS NO-TPD NO conversion methane conversion

150 mV脉冲驱动交流量子电压芯片的研制

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计量学报 2025年第1期46卷 25-29页

作者：徐思思程千硕李晓宇韩琪娜钟青李劲劲曹文会钟源中国计量大学计量测试工程学院浙江杭州310018 中国计量科学研究院北京100029 哈尔滨工业大学黑龙江哈尔滨150001

超导芯片是脉冲驱动任意波形合成系统(JAWS)系统的核心。由中国计量科学研究院(NIM)自行研制的JAWS芯片,采用渐变波导结构以补偿阵列中不同位置的约瑟夫森结所感受到的差异化驱动脉冲强度,通过测试芯片的I-V特性曲线,以及使用脉冲序列... 详细信息

超导芯片是脉冲驱动任意波形合成系统(JAWS)系统的核心。由中国计量科学研究院(NIM)自行研制的JAWS芯片,采用渐变波导结构以补偿阵列中不同位置的约瑟夫森结所感受到的差异化驱动脉冲强度,通过测试芯片的I-V特性曲线,以及使用脉冲序列驱动芯片合成交流信号来验证芯片的电学性能。测试结果表明:芯片中集成的8000个约瑟夫森结全部正常工作,成功研制了有效值150 mV交流、1 kHz量子电压信号输出的超导芯片,高次谐波的幅值比基频低105 dB。

关键词：电学计量量子电压芯片电压标准脉冲驱动渐变波导约瑟夫森结

The Effect of Soil Enzymes and Polysaccharides Secreted by the Roots of Salvia miltiorrhiza Bunge under Drought,High Temperature,and Nitrogen and Phosphorus Deficits

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 119-135页

作者： Yong Qin xiaoyu li Yanhong Wu Hai Wang Guiqi Han Zhuyun Yan State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China Chengdu University of Traditional Chinese MedicineChengduChina School of Pharmacy Chengdu University of Traditional Chinese MedicineChengduChina School of Medical Technology Chengdu University of Chinese MedicineChengduChina

Root exudates serve as crucial mediators for information exchange between plants and soil,and are an important evolutionary mechanism for plants’adaptation to environmental *** this study,15 different abiotic stress models were established using various stress factors,including drought(D),high temperature(T),nitrogen deficiency(N),phosphorus deficiency(P),and their *** investigated their effects on the seedling growth of Salvia miltiorrhiza Bunge and the activities of Solid-Urease(S-UE),Solid-Nitrite Reductase(S-NiR),Solid-Nitrate Reductase(S-NR),Solid-Phosphotransferase(S-PT),and Solid-Catalase(S-CAT),as well as the contents of polysaccharides in the culture *** results showed that the growth of *** was inhibited under 15 stress *** them,13 stress conditions increased the root-shoot *** 15 stress conditions significantly reduced the activity of S-NR,two combinations significantly improved the activity of S-NIR,they were synergistic stresses of high temperature and nitrogen deficiency(TN),and synergistic stresses of drought and nitrogen deficiency(DN)(p<0.05).The activity of S-UE was significantly improved under N,D,T,synergistic stresses of drought and high temperature(DT),DN,synergistic stresses of drought and phosphorus deficiency(DP),and synergistic stresses of high temperature,nitrogen,and phosphorus deficiency(TNP)stress conditions(p<0.05).Most stress combinations reduced the activity of S-PT,but D and T significantly improved it.(p<0.05).The N,DN,and TN stress conditions significantly reduced S-CAT *** P,DT,and synergistic stresses of drought,high temperature,and phosphorus deficiency(DTP)significantly decreased the total polysaccharide content of the soil(p<0.05).The research suggested that abiotic stress hindered the growth of *** and altered the behavior of root *** regulated the secretion of several substances in response to various abiotic stresses,including soil ni

关键词： Abiotic stress Salvia miltiorrhiza soil enzymes total polysaccharides soil carbon sequestration

Co-optimization of energy management and eco-driving considering fuel cell degradation via improved hierarchical model predictive control

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Green Energy and Intelligent Transportation 2024年第6期3卷 1-14页

作者： Caixia liu Yong Chen Renzong Xu Haijun Ruan Cong Wang xiaoyu li School of Mechanical Engineering Hebei University of TechnologyTianjin 300130China School of Mechanical Engineering Guangxi UniversityGuangxi 530004China Institute for Clean Growth&Future Mobility Coventry UniversityUK Tianjin Key Laboratory of New Energy Automobile Power Transmission and Safety Technology School of Mechanical EngineeringHebei University of TechnologyTianjin 300130China School of Vehicle and Mobility Tsinghua UniversityBeijing 100190China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of TechnologyTianjin 300130China

An advanced eco-driving technology is widely recognized as having enormous potential to reduce the vehicle fuel ***,most research on eco-driving focuses on the stability and safety for vehicle operating while disregarding its comfort and *** meet the requirements for safety and comfort,at the same time,enhance the economic performance of the vehicles,an improved hierarchical model predictive control cooperative optimization strategy is proposed for fuel cell hybrid electric vehicle with car-following ***,the upper-level model predictive controller controls the velocity,inter-vehicle distance and acceleration to guarantee safety and comfort for *** to the velocity information obtained from the upper model predictive controller,the lower-level improved model predictive controller considers the impact of disturbance changes on vehicle economy and aims to minimize the vehicle operating cost considering fuel cell degradation,so as to allocate energy ***,the enhancement of economic performance of proposed strategy is verified with the results of comparative study that 3.09%economic improvement on the premise of assuring safety and comfort of driving.

关键词： Fuel cell hybrid electric vehicle Hierarchical model predictive control Car-following Eco-driving

Mechanical vibration modeling and characterization of a plastic-cased lithium-ion battery

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Green Energy and Intelligent Transportation 2022年第2期1卷 9-18页

作者： xiaoyu li Zhijia Huang Wen Hua Lalith Rao Yong Tian Jindong Tian College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen518060China National Engineering Laboratory for Electric Vehicles School of Mechanical EngineeringBeijing Institute of TechnologyBeijing100081China Center for Automotive Research Department of Mechanical and Aerospace EngineeringThe Ohio State UniversityColumbusOH 43210United States Guangdong Laboratory of Artificial Intelligence and Digital Economy(SZ) Shenzhen UniversityShenzhen518060China

Batteries often show the coupling change of multiple physical field characteristic parameters in the charging or discharging *** battery modeling and characterization methods mainly focus on electrical or thermal *** that battery state change can cause a change in the mechanical structure,research on the vibration characteristic modeling and characterization of a plastic-cased lithium-ion battery is carried *** analyzing the mechanical structure of the battery,the first principles modeling method is selected to model the battery's mechanical *** vibration data in the process of battery charging and discharging are measured by a laser Doppler vibrometer(LDV).The obtained experimental data are used to identify the mechanical parameters of the *** on the experimentael results,the root mean square error(RMSE)of the frequency domain amplitude fitting result of the model is less than 11.36%.The effectiveness of the battery mechanical vibration model is *** model and the characterization method provide tools for nondestructive battery state evaluation.

关键词： lithium-ion battery Mechanical vibration Modeling Characterization

Design and experiment of corn low damage threshing device based on DEM

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International Journal of Agricultural and Biological Engineering 2023年第3期16卷 55-63页

作者： xiaoyu li Yuefeng Du Enrong Mao Yan’an Zhang Lei liu Dafang Guo Beijing Key Lab Optimized Design for Modern Agricultural Equipment China Agricultural UniversityBeijing 100083China College of Engineering China Agricultural UniversityBeijing 100083China

Kernel broken rate is an important index to evaluate the maize kernel direct harvesting *** view of the problem of the high kernel broken rate in the present maize harvester,a new threshing cylinder was designed in this *** device utilized rasp bar to achieve low damaged maize ears *** order to determine the structure and working parameters of threshing device,the“crop-crop”contact model and the“crop-mechanical”interaction system were established and analyzed based on the discrete element method first,and the mathematical expressions of the related kinematic response of maize kernel under the external force were ***,the structure parameters of rasp bar were studied through EDEM simulation experiment,and the working parameters were determined through test-bed ***,the simulation experiment results and test-bed experiment results were verified through field *** results showed that when the threshing cylinder speed was 356 r/min,the concave clearance was 40 mm,the installation distance of rasp bar was 250 mm with 50Mn steel,and the feeding amount was 8 kg/s,the kernel broken rate was 1.93%,which satisfied the requirements of maize harvest *** study proved that the DEM(Discrete Element Method)can be adopted to guide the optimization design of mechanical structure,and it has certain value for the research and development of operation equipment of other agricultural crops.

关键词： DEM maize threshing low damage harvesting kernel broken rate simulation

Design and experiment of automatic garlic seed directing device

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 85-93页

作者： Aijun Geng xiaoyu li Jialin Hou Ji Zhang Zhilong Zhang Jun Chong College of Mechanical and Electrical Engineering Shandong Agricultural UniversityTaian 271018ShandongChina Shandong Key Laboratory of Horticultural Machinery and Equipment Taian 271018ShandongChina Ji'nan Huaqing Agricultural Machinery Technology Co. Ltd.Ji'nan 251600ShandongChina

Garlic planting requires a single seed with a scaly bud upward and *** this study,an automatic garlic seed directing device was designed for auxiliary garlic seeding by utilizing a seed placed funnel,a correcting mechanism,and an automatic control *** factors influenced device performance:characteristics of garlic seeds,limited notch diameter of the seed placed funnel,and funnel taper of the seed placed *** most optimal structural parameters of the seed placed funnel were determined via theoretical *** research samples of Lanling and Jinxiang garlic were divided into three groups according to their respective sizes.3D design software(Solidworks)was used to simulate the above three factors and analyze their rules of *** obtained simulation results demonstrated that the suitable range of funnel taper and limited notch diameter of seed placed funnel for the three groups of seed were from 40°to 60°and 6-8 mm,*** bench test showed that when the funnel taper was 60°and the limited notch diameter was 10 mm,the success rates of the three groups’seeds in terms of scaly bud directing were 89.8%,91.6%and 96.6%respectively,which satisfied the agricultural requirements of garlic ***,the corresponding results may promote the study and improvement of garlic intelligent planting equipment.

关键词： garlic garlic seed directing simulation and analysis automatic control

The Complete Sequence of Mitochondrial COII Gene of Fenneropenaeus chinensis and Its Applicability as a Marker for Phylogenetic Analysis

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Journal of Ocean University of China 2007年第2期6卷 187-192页

作者： YU Shanshan KONG xiaoyu li Yulong XU Hui Key Laboratory of Mariculture of Ministry of Education Ocean University of China Qingdao 266003 P. R. China

The complete mitochondrial cytochrome oxidase subunit Ⅱ （COⅡ） gene of Penaeinae shrimp Fenneropenaeus chinensis was cloned and sequenced. The gene is 688 bp in length and codes for 229 amino acids. It shows 83.2%, 87.0% and 83.8% sequence similarity to Marsupenaeus Japonicus, Penaeus monodon and Farfantepenaeus notialis, respectively. The A＋T content of the whole gene and that at the third position of codons are 64.7% and 78.2%, respectively. The phylogenetic relationship between F. chinensis and three other species representing genera Farfanatepenaeus, Marsupenaeus and Penaeus was analyzed. Results showed that the genetic distances among the four taxa ranged from 0.144 0 to 0.200 5, exceeding those estimated with COⅠ and partial 16S rRNA gene sequences among Marsupenaeus, litopenaeus and Melicertus, and being therefore larger than the value among subgenera. It has been suggested that the COⅡ gene has a faster evolutionary rate than that of the COⅠ gene and partial 16S rRNA gene and could be used for phylogenetic analysis at genus or species level. The results of the present study indicated that Farfantepenaeus, Fenneropenaeus, Marsupenaeus and Penaeus are at a higher phylogenetic level than subgenus, which supports the opinion of the elevation of phylogenetic status of the four subgenera to genus level.

关键词： Fenneropenaeus chinensis COⅡ gene phylogenetic analysis

Flavonoids and ROS Play Opposing Roles in Mediating Pollination in Ornamental Kale （Brassica oleracea var. acephala）

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Molecular Plant 2017年第10期10卷 1361-1364页

作者： Xingguo Lan Jia Yang Kumar Abhinandan Yuzhe Nie xiaoyu li Yuhua li Marcus A. Samuel College of life Sciences Northeast Forestry University Harbin Heilongjiang 150040. P R China Department of Biological Sciences University of Calgary Calgary AB T2N 1N4. Canada

Dear Editor,In most flowering plants, the stigma of the flower represents the barrier that prevents any unrelated or incompatible （genetically similar） pollen from germination and fertilizing the ovule, leading to either defective or genetically unfavorable embryos. In Brassicaceae, self-incompatibility （SI） is a genetic mechanism in the stigmas that can discern compatible versus incompatible mate （pollen）, in turn, rejecting self or incompatible pollen, while allowing non-self or compatible pollen to develop successfully to fertilize the ovules. Thus, stigmas have evolved complex mechanisms and specialized proteins to reject incompatible mates and to recognize and accept compatible pollen （Doucet et al., 2016）. The fact that SI has been shown to exclusively operate in the stigmas temporally before and during anthesis （Kandasamy et al., 1993） indicates that multiple metabolic pathways essential for pollination exist in these stigmatic papillary cells.

关键词： Flavonoids ROS Play Opposing Roles Mediating Pollination Ornamental Kale Brassica oleracea var acephala

A water-stable lanthanide-coordination polymer with free Lewis site for fluorescent sensing of Fe^(3+)

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Chinese Chemical Letters 2019年第1期30卷 75-78页

作者： Wenhe Wang Qiang Gao xiaoyu li Jianhong Wang Chaopeng Wang Yinghui Zhang Xianhe Bu Department of Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Nankai University School of Materials Science and Engineering TKL of Metal- and Molecule-Based Material Chemistry Nankai University

A new fluorescent coordination polymer(NKU-115) was constructed under solvothermal condition based on Tb^(3+)ion and H_2L(5-(4 H-1,2,4-triazol-4-yl) benzene-1,3-dicarboxylic acid) ligand, featuring high solvent and water stability. Luminescent investigations revealed that NKU-115 shows fluorescence quenching response toward Fe^(3+)in aqueous solution and the mechanism of quenching was analyzed.

关键词： Lanthanide-based coordination polymers Fluorescent sensing Aqueous solution Lewis site Iron ion