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近红外光谱技术在谷物检测中的应用研究进展

食品科学 2025年第3期46卷 267-273页

作者：王子熙沈群赵卿宇中国农业大学食品科学与营养工程学院国家果蔬加工工程技术研究中心国家粮食产业(青稞深加工)技术创新中心国家粮油标准研究验证测试中心北京100083

谷物作为人类的主要食物,富含多种关键营养成分,如水分、蛋白质、脂肪以及碳水化合物等。但由于谷物长期储存、霉菌污染和含异种粮粒等情况会严重影响谷物品质,危害粮食安全。因此,准确快速地检测谷物的营养成分、理化性质、霉菌污染以... 详细信息

谷物作为人类的主要食物,富含多种关键营养成分,如水分、蛋白质、脂肪以及碳水化合物等。但由于谷物长期储存、霉菌污染和含异种粮粒等情况会严重影响谷物品质,危害粮食安全。因此,准确快速地检测谷物的营养成分、理化性质、霉菌污染以及其他方面对于食品质量控制和营养评估至关重要。近红外光谱技术作为一种快速、非破坏性的检测方法,近年来在粮食分析领域得到广泛应用。本文旨在综述近红外光谱技术在不同谷物营养成分(淀粉、脂肪、蛋白质、生物活性物质等)、理化特性(淀粉黏度特性值、硬度、粉质特性等)、霉菌污染以及其他(新陈度、品种鉴别、重金属和农药残留等)方面的应用现状,总结和比较常见模型算法的优点与不足,并提出目前近红外光谱技术在谷物检测中存在的问题以及未来发展方向,以期为进一步完善近红外光谱技术在谷物检测方面提供一定的参考依据。

关键词：谷物近红外光谱营养成分理化性质霉菌污染

EXPLICIT CONSTRUCTION FOR LOCAL ISOMETRIC IMMERSIONS OF SPACE FORMS

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Chinese Annals of Mathematics,Series B 2003年第1期24卷 97-110页

作者： HE qun shen YIBING Department of Applied Mathematics Tongji University Shanghai 200092 China.Department of Mathematics West Brook Zhejiang University Hangzhou 310028 China.

By using Darboux transformations, the authors give the explicit construction for local iso-metric immersions of space forms Mn(c) into space forms M2n-1(c + ε2) via purely algebraicalgorithm.

关键词： Space form Isometric immersion Darboux transformation

Novel gripper module and method for automated assembly of miniature parts

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Advances in Manufacturing 2023年第2期11卷 295-310页

作者： Zhi-Yong Zhang Xiao-Dong Wang Tong-qun Ren Tian-lun Jin Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian116024LiaoningPeople's Republic of China Key Laboratory for Precision and Non-traditional Machining of Ministry of Education Dalian University of TechnologyDalian116024LiaoningPeople's Republic of China

During assembly process,the miniature part needs to be fixed in its assembly *** some occasions where adhesive is used,the joining force is not established due to the adhesive curing process,in that case the locking of parts is *** locking is difficult to meet the increasing demand for mass *** solve this problem and realize fully automatic assembly,a novel gripper module was designed and corresponding locking method was *** to the functional integration,the gripper module is capable of manipulating and locking the *** module is integrated into the assembly system and plays a crucial role in automatic *** locking method for automatic assembly is based on the integration of the part picking up and the locking unit *** being placed accurately at its desired position,the miniature part can be automatically locked by releasing the locking *** innovative structure and mechanism of the gripper module convert the spring force into the locking force of the miniature part,ensuring non-rigid locking and suitable small locking *** principle,flexibility and limitations of the proposed method were clarified in ***,an effective compensation strategy was used to achieve accurate and stable pickup of the part,which increased the reliability of the assembly *** automatic locking,the disturbances to the part due to the eccentric load were *** effectiveness of the gripper module and proposed method was verified by *** results indicated that the modular system integrated with the gripper module could meet the requirements of fully automatic *** locking is replaced by automatic locking,and workers are liberated from tedious manual *** improvement of automation level enables assembly equipment to be applied to mass production scenarios.

关键词： Fully automatic assembly Miniature parts Automatic locking Gripper module

Phase noise approximation analysis for the OFDM system

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 95-98,107页

作者： TANG Jing shen Shu-qun Wireless Technique Innovation Institute Key Laboratory of UniversalWireless Communication Ministry of Education Beijing University of Postsand Telecommunications Beijing 100876 China

The influence of phase noise（PN） present at the access point（AP） and mobile terminator（MT） may degrade the performance in orthogonal frequency division multiplexing （OFDM） system, because the OFDM system is sensitive to the PN. The method of PN approximation based on the PN power spectrum was proposed to combat the influence of the PN present. The idea of the PN cancellation is the PN is approximated for the sum of the different frequency between the AP and the MT as well as Doppler shift supposing that the fixed different frequency during several OFDM symbols are identical, so the variable phase may be considered as the combination of the fixed partition and the random partition. The approximation method is utilized to remove the fixed and the random phase partition so that the signal-to-noise ratio （SNR） may be improved. The analysis and the simtilation proposed show that the method may effectively improve the performance of the OFDM system.

关键词： inter-carrier interference(ICI) phase noise cancellation common phase error (CPE)

Isoparametric hypersurfaces in Funk spaces

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Science China Mathematics 2017年第12期60卷 2447-2464页

作者： HE qun YIN SongTing shen YiBing School of Mathematical Sciences Tongji University Department of Mathematics and Computer Science Tongling University Department of Mathematics Zhejiang University

Funk metrics are a kind of important Finsler metrics with constant negative flag curvature. In this paper, it is proved that any isoparametric hypersurface in Funk spaces has at most two distinct principal curvatures.... 详细信息

关键词： Finsler-Laplacian isoparametric hypersurfaces Funk metric principal curvature

全谷物及杂豆添加量在小鼠与人体间剂量换算分析

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食品科学 2025年第2期46卷 118-125页

作者：支莉朱益清赵亮星陈睿赵卿宇王超薛勇沈群国家粮食产业(青稞深加工)技术创新中心国家粮油标准测试研究中心中国农业大学食品科学与营养工程学院北京100083

适量摄入全谷物及杂豆可以改善糖代谢和脂代谢,但摄入量过高可能产生不利影响。由于缺乏相应的换算关系,小鼠饲料中的摄入量无法直接作为人群摄入量的参考。本文介绍小鼠饲料中常见的全谷物及杂豆的添加量,并通过等效系数法、比表面积... 详细信息

适量摄入全谷物及杂豆可以改善糖代谢和脂代谢,但摄入量过高可能产生不利影响。由于缺乏相应的换算关系,小鼠饲料中的摄入量无法直接作为人群摄入量的参考。本文介绍小鼠饲料中常见的全谷物及杂豆的添加量,并通过等效系数法、比表面积法、体型系数法、食物比重法、体表面积指数法、能量换算法和营养素换算法探讨了小鼠饲料中全谷物及杂豆添加量与人群膳食推荐量之间的剂量效应关系。研究表明,当人群全谷物及杂豆推荐摄入量为50~150 g时,相当于在每日进食量为3 g的小鼠饲料中添加5%~50%的全谷物及杂豆。对于小鼠而言,饲料中全谷物及杂豆的添加量超过50%可能存在过量摄入的风险。本研究为未来建立全谷物及杂豆在小鼠饲料添加量与人群推荐摄入量之间的换算关系提供了重要参考。

关键词：剂量换算全谷物杂豆体表面积

Simulation and analysis of co-phasing errors of the segmented primary mirror tiled by hexagonal segments in LOT

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Research in Astronomy and Astrophysics 2021年第10期21卷 37-45页

作者： Shi-Dong shen Xiang-qun Cui Yong Zhang National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China University of the Chinese Academy of Sciences Beijing 100049China

In this paper,co-phasing errors of a segmented primary mirror tiled by hexagonal segments are successfully calculated for the 12-meter Large aperture Optical/infrared Telescope(LOT).Co-phasing errors including out-of-plane errors are simulated separately and comprehensively based on several software simulation *** simulation results show that the Strehl Ratio(SR)of LOT is larger than 0.8 when the RMS value of tip-tilt obeying a normal distribution is less than 0.018 arcsec,and the SR of LOT is larger than 0.8 when the RMS value of piston obeying a normal distribution is less than 40 ***,simulation results of Zemax show that the SR of LOT is larger than 0.8 when the RMS value of tip-tilt obeying a normal distribution is less than 0.02 arcsec,and the SR of LOT is larger than 0.8 when the RMS value of piston obeying a normal distribution is less than 40 *** simulation results successfully lay a solid foundation for LOT(especially the segmented primary mirror with active optics).

关键词： methods:analytical techniques:miscellaneous telescopes

Adsorption of cationic dyes from aqueous solution using hydrophilic silica aerogel via ambient pressure drying

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2467-2473页

作者： qun Liu Yuan Liu Zhihua Zhang Xiaodong Wang Jun shen College of Science University of Shanghai for Science and TechnologyShanghai 200093China Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Department of Physics Science and Engineering of Tongji UniversityShanghai 200092China

In order to remove the organic dyes of textile waste water,the silica aerogel was successfully prepared by using E-40 as a novel precursor and then dried in ambient *** synthesized sample was verified by Scanning Electron Microscopy(SEM)and Fourier Transform Infrared Spectroscopy(FTIR).After calcining,the hydrophilic silica aerogel(HSA)was used as adsorbent to remove Methylene Blue(MB),Malachite Green(MG),and Gentian Violet(GV)from aqueous *** effects of initial concentration of dyes and adsorbent dosage on the adsorption process were *** was found that HSA showed excellent adsorption capacities,the maximum percentage of removal dyes could reach 98%.Herein,the Langmuir,Freundlich and de Boer-Zwikker isotherm modes were employed to discuss the adsorption *** results indicated that the de Boer–Zwikker model can effectively describe the adsorption ***,the HSA could be utilized as the recyclable adsorbent in degradation experiment,after five cycles,no obvious loss of adsorption capacity was *** an efficient,low-cost,environmental friendly and recyclable adsorbent,silica aerogel is expected to be used for dyes removal.

关键词： Silica aerogel Adsorbents E-40 Waste water Adsorption Cationic dyes

On the first eigenvalue of Finsler manifolds with nonnegative weighted Ricci curvature

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Science China Mathematics 2014年第5期57卷 1057-1070页

作者： YIN SongTing HE qun shen YiBing Department of Mathematics Tongji University Department of Mathematics and Computer Science Tongling University Department of Mathematics Zhejiang University

We prove that for a compact Finsler manifold M with nonnegative weighted Ricci curvature,if its first closed(***)eigenvalue of Finsler-Laplacian attains the sharp lower bound,then M is isometric to a circle(resp.a segment).Moreover,a lower bound of the first eigenvalue of Finsler-Laplacian with Dirichlet boundary condition is also *** generalize the corresponding results in recent literature.

关键词： Finsler-Laplacian the first eigenvalue Ricci curvature S curvature