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Effects of ultrasonic-assisted extraction on bioactive compounds,volatile flavors and antioxidant activities of vine tea water extracts

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Traditional Medicine Research 2025年第1期10卷 73-81页

作者： Xiao-Long Zhou Wei-Jin Jiang Ji Yu mao-jun yao Yun-Tong Li Hunan Provincial Key Laboratory of Research Resource Mining and High-valued Utilization on Edible&Medicinal PlantCollege of Chemistry and Chemical EngineeringJishou UniversityJishou 416000China Hunan Gaoge Dairy Co. Ltd.Changsha 410000China

Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in *** vine tea processing,a large amount of broken tea is produced,which has low commercial ***:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea ***:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid *** chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted ***,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE *** vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant ***:The findings suggest that extraction methods signi

关键词： vine tea dihydromyricetin ultrasonic-assisted extraction volatile aroma components

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A dual-site Fe-based catalyst for efficient ammonia synthesis under mild conditions

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Science China Chemistry 2025年

作者： Shiyong Zhang Mingyuan Zhang Tianhua Zhang Jizhen Sun Jiaxin Li Kailin Su Ruishao mao yanliang Zhou Xuanbei Peng yangyu Zhang jun Ni Bingyu Lin Xiuyun Wang Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou University Qingyuan Innovation Laboratory

Achieving green ammonia （NH3） synthesis requires developing effective catalysts under mild ***,the competitive adsorption of N2and H2,as well as the strong binding of N-containing intermediates on the catalyst,greatly inhibits the active sites for efficient ***,we constructed a series of ZrH2-modified Fe catalysts with dual active sites to address these issues and realized efficient NH3synthesis under mild *** study shows that ZrH2can not only provide active sites for H2activation but also transfer electrons to Fe sites for accelerating *** interaction between Fe and ZrH2over 40ZrH2-Fe leads to a decrease in work function and a downward shift of the d-band center,which is conducive to N2activation and NH3desorption,*** utilization of distinct sites for activating different reactants can avoid the competitive adsorption of N2and H2,leading to excellent NH3synthesis activity of the 40 wt.%ZrH2-mediated Fe *** a result,40ZrH2-Fe exhibits a high NH3synthesis rate of 23.3 mmol g-1cath-1at 400°C and 1 MPa and robust stability during100 h time-on-stream.

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Numerical Simulation and Experimental Study of an Ultrasonic Waveguide for Ultrasonic Casting of 35CrMo Steel

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Journal of Iron and Steel Research International 2016年第8期23卷 772-777页

作者： Gen LIANG Chen SHI ya-jun ZHOU Da-heng mao College of Mechanical and Electrical Engineering Central South University State Key Laboratory of High Performance Complex Manufacturing Central South University

To achieve ultrasonic casting of 35 CrMo steel,the waveguide unit for introducing ultrasound into liquid steel was studied numerically and *** structure and length of the ultrasonic waveguide were optimized by modal *** simulation results showed that a T-shaped waveguide unit matched the vibrational system better than an L-shaped *** performance of T-shaped waveguide unit was optimized when the length of the ultrasound radiator was 135 *** performance of the T-shaped waveguide unit was investigated in ultrasonic casting experiments,and the effect of ultrasound on the microstructure of 35 CrMo steel was *** experimental results showed that the T-shaped waveguide was able to successfully introduce ultrasound into the 35 CrMo *** addition,the use of a silicon nitride ceramic radiator avoided high-temperature corrosion in the molten *** microstructure of the treated area was significantly refined and equiaxed grains were *** results represented a novel method for ultrasonic casting of steel.

关键词： waveguide shaped ultrasonic equiaxed nitride refined length molten grains ceramic

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Effects and Mechanisms of RE on Impact Toughness and Fracture Toughness of Clean Heavy Rail Steel

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Journal of Iron and Steel Research International 2011年第3期18卷 52-58页

作者： LIU Cheng-jun HUANG ya-he JIANG mao-fa School of Materials and Metallurgy Northeastern UniversityShenyang 110004LiaoningChina

Clean high carbon heavy rail steel was prepared by the process of vacuum induction furnace smelting,forging and *** of RE on the impact toughness and fracture toughness for clean high carbon steel were *** addition,the appropriate range of RE content for clean high carbon steel was *** the austenite grain size and pearlite lamellar spacing decreased due to small amount of RE,consequently the impact toughness and fracture toughness were improved *** the RE content exceeded a critical value,the pearlite lamellar spacing was increased,because RE was segregated on the austenite grain boundaries,damaged the orientation relationship of pearlite transformation,caused the disorder growth and morphology degenerating of *** the increasing of RE content,both the impact toughness and fracture toughness of clean high carbon steel were gradually increased at first and then *** was found that when the RE content was between 0.0081% and 0.0088%,both the impact toughness and fracture toughness of clean high carbon heavy rail steel were the *** maximum ballistic work was 21.2 J（20 ℃） and 12.2 J（-20 ℃）,*** maximum plane-strain fracture toughness was 45.67 MPa·m1/2（20 ℃） and 37.04 MPa·m1/2（-20 ℃）,respectively.

关键词： rare earth high carbon steel heavy rail steel clean steel impact toughness fracture toughness

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A novel high precision Doppler frequency estimation method based on the third-order phase-locked loop

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Research in Astronomy and Astrophysics 2021年第9期21卷 83-90页

作者： Tao Deng mao-Li Ma Qing-Hui Liu ya-jun Wu Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

In deep space exploration,many engineering and scientific requirements require the accuracy of the measured Doppler frequency to be as high as *** our paper,we analyze the possible frequency measurement points of the third-order phase-locked loop(PLL)and find a new Doppler measurement *** on this finding,a Doppler frequency measurement algorithm with significantly higher measurement accuracy is *** the actual data processing,compared with the existing engineering software,the accuracy of frequency of 1 second integration is about 5.5 times higher when using the new *** improved algorithm is simple and easy to *** improvement can be easily combined with other improvement methods of PLL,so that the performance of PLL can be further improved.

关键词： Doppler frequency measurement:deep space exploration:carrier tracking:phase locked loop:high precision

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Remarkably Improved Gas Separation Performance of Polyimides by Forming“Bent and Battered”Main Chain Using Paracyclophane as Building Block

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Chinese Journal of Polymer Science 2023年第10期41卷 1617-1628页

作者： Lu-jun Huang ya-Tao Weng Aqib Raiz Zhi-Jie mao Xiao-Hua Ma State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin300387China School of Materials Science and Engineering Tiangong UniversityTianjin300387China Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science&Technology Normal UniversityNanchang330013China

The design and development of highly permeable,selective and stable polymer membranes are great challenges in the gas separation ***,we constructed two intrinsic microporous polyimides(6FPCA and 6FMCA)derived from two isometric diamines(PCA and MCA),which were synthesized by palladium catalyzed C—N coupling *** PCA and MCA diamines contain a hollow beaded structure of 2,2′-paracyclophane as a building block with a specified window size of 3.09Å.The chemical structures of monomers,polyimides were confirmed by NMR,FTIR,and elementary analysis.6FPCA and 6FMCA exhibit good solubility,excellent thermal stability,and mechanical properties.6FPCA exhibits much larger microporosity(434 versus 120 m2·g−1),FFV(0.22 versus 0.15),d-spacing(6.9 versus 5.9Å),and over 10 times higher permeability with a very little decrease in selectivity than the corresponding polyimide(6FpA)with a plane structure,which remarkably increased their separation performance from far below the 2008 Robeson Upper bounds to reach these limitations for O2/N2 and CO2/***,the 6FPCA also demonstrates good plasticization resistance,moderate aging properties,and high CO2/CH4 mixed-gas separation *** results indicate that paracyclophane subunit can be successfully incorporated into polymers to enhance their ultra-microporosity and separation properties,which open a new avenue for developing high performance gas separation membranes with topological ultra-micropores.

关键词： Polyimide of intrinsic microporosity 2,2'-Paracyclophane Molecular intrinsic microporosity Gas separation Permeability/selectivity trade-off

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Effect of cerium addition on microstructure and mechanical properties of as-cast high grade knives steel

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Journal of Iron and Steel Research International 2022年第12期29卷 1986-1994页

作者： Xi-ya Qiao Xiao Han Zhi-jun He Zhen Zhuang Xin yang Fei-xiong mao School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Ningbo Key Laboratory of Marine Protection Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201ZhejiangChina

The carbides and mechanical properties of as-cast high grade knives steel with and without cerium(Ce)addition were *** as-cast microstructure of the steel,the size of carbide precipitation,carbide morphology,and mechanical properties were systematically studied through optical microscopy,scanning electron microscopy,and X-ray ***,through the Equilib module of the FactSage thermodynamics software,the changes in the precipitation type of the inclusions with Ce during the solidification of the steel were *** results indicate that the rare earth Ce is added into the steel to refine the as-cast microstructure of the *** types of inclusions in the steel are changed by the addition of *** precipitated carbide morphology changes from a complex rod shape to a relatively single lamellar *** rare earth inclusions formed in steel by a moderate addition of Ce can be severed as the core of heterogeneous nucleation of carbides,which reduce the size of carbide precipitation,promote the uniform distribution of carbide in the as-cast steel,and improve the mechanical properties of the as-cast high grade knives steel.

关键词： Carbide Microstructure Mechanical property Cerium High grade knives steel

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排水降噪沥青混合料SMAp的研究和应用

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价值工程 2025年第1期44卷 59-61页

作者：兰亚军中铁十一局集团第二工程有限公司十堰442000

随着城市化步伐的加快、道路车辆数量的增加,道路噪音和排水问题已成为影响城市生活质量的重要因素,急需研发出新型的沥青混合料来予以应对。排水降噪沥青混合料作为一种新沥青,其独特的结构特征与材料特性赋予了自身卓越的排水降噪性能... 详细信息

随着城市化步伐的加快、道路车辆数量的增加,道路噪音和排水问题已成为影响城市生活质量的重要因素,急需研发出新型的沥青混合料来予以应对。排水降噪沥青混合料作为一种新沥青,其独特的结构特征与材料特性赋予了自身卓越的排水降噪性能,既能够有效地将雨水从路面排出,提高交通安全,缓解城市排水系统的压力,又能减轻路面和汽车轮胎之间的空气泵送效应,降低车辆噪声污染。基于此,本文结合无岳高速公路项目,探讨了排水降噪沥青混合料SMAp的研发技术以及应用方法,旨在给技术人员提供参考。

关键词：排水降噪沥青路面沥青混合料SMAp 耐久性

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Correlating Photovoltaic Performance of Dye-Sensitized Solar Cell to the Film Thickness of Titania via Numerical Drift-Diffusion Simulations

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Chinese Journal of Chemical Physics 2016年第6期29卷 735-741,I0002页

作者： Yu-dan Wang Zhe Sun ya-jun Ren yan Zhang mao Liang Song Xue TianjinKeyLaboratoryofOrganicSolarCellsandPhotochemicalConversion SchoolofChemistryChemicalEnEineerinETianjinUniversityofTechnologyTianjin300384China SchoolofElectricEngineering TianjinUniversityofTechnologyTianjin300384China

The thickness of TiO2 film is vital to realize the optimization on photovoltaic performance of dye sensitized solar cells （DSSCs）. Herein, the process of charge separation in DSSCs was simulated by using a drift-diffusion model. This model allows multiple-trapping diffu- sion of photo-generated electrons, as well as the back reaction with the electron acceptors in electrolyte, to be mimicked in both steady and non-steady states. Numerical results on current-voltage characteristics allow power conversion efficiency to be maximized by varying the thickness of TiO2 film. Charge collection efficiency is shown to decrease with film thick- ness, whereas the flux of electron injection benefits from the film thickening. The output of photocurrent is actually impacted by the two factors. Furthermore, recombination rate constant is found to affect the optimized film thickness remarkably. Thicker TiO2 film is suitable to the DSSCs in which back reaction is suppressed sufficiently. On the contrary, the DSSCs with the redox couple showing fast electron interception require thinner film to alleviate the charge loss via recombination. At open circuit, electron density is found to decrease with film thickness, which engenders not only the reduction of photovoltage but also the increase of electron lifetime.

关键词： Dye-sensitized solar cells Titania Film thickness Simulation

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Experiments of effects of inlet-air distortion on aerodynamic performance in transonic compressor

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航空动力学报 2013年第5期28卷 1047-1056页

作者： LI mao-yi YUAN Wei LU ya-jun SONG Xi-zhen LU Li-peng National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Energy and Power EngineeringBeijing University of Aeronautics and Astronautics

The inlet-air distortion which was caused by high angle-of-attack flight was simulated by *** were conducted on a transonic axial-flow compressor's rotor at 98% rotating *** flow-field characteristics and mechanism of performance degradation were analyzed in *** compressor inlet was divided into four sectors at circumference under inlet-air *** were undistorted sector,transition sector A where the rotor was rotating into the distortion sector,distorted sector and transition sector B where the rotor was rotating out of the distortion *** experimental results show that compared with undistorted sector,there is a subsonic flow in transition sector A,so the pressure ratio is decreased by a large margin in this ***,the shock wave is enhanced in distortion sector and transition sector B,and thus the pressure ratio increases in these *** of the different works at circumference,the phase angle of total pressure changes 90° when the inlet total pressure distortion passes through compressor *** addition,the frequency and amplitude of disturbances in front of the rotor strengthenes under inlet distortion,so the unstable flow would take place in *** addition,the position of stall inception is in one of the transition sectors.

关键词： plugboard simulator inlet-air distortion transonic axial-flow compressor shock wave disturbance

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