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立铣刀磨削加工的棒料装夹偏差补偿技术

工具技术 2024年第7期58卷 153-156页

作者：杨润强高冬冬唐文李西安精雕精密机械工程有限公司

刀具棒料装夹偏差是影响刀具磨削精度不可忽视的重要因素。本文基于在机测量探测刀具棒料上各采样点位置的装夹偏差,建立了理论刀具刃线上点的偏差估算方法,在实际磨削加工时,将偏差值反向补偿至磨削轨迹,从而减小刀具的装夹偏差对刀具... 详细信息

刀具棒料装夹偏差是影响刀具磨削精度不可忽视的重要因素。本文基于在机测量探测刀具棒料上各采样点位置的装夹偏差,建立了理论刀具刃线上点的偏差估算方法,在实际磨削加工时,将偏差值反向补偿至磨削轨迹,从而减小刀具的装夹偏差对刀具磨削精度的影响。通过试验磨削四刃平底刀和双刃球刀,在棒料装夹偏差较大的情况下,采用补偿的方式能够提高刀具外形磨削精度。

关键词：立铣刀装夹偏差在机测量磨削补偿

真空冷冻干燥不同升温程序对蓝莓干燥特性及品质影响

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核农学报 2024年第1期38卷 84-92页

作者：于蕊杨慧珍李大婧肖亚冬聂梅梅刘春菊杨润强金鹏南京农业大学食品科技学院江苏南京210095 江苏省农业科学院农产品加工研究所江苏南京210014

不同真空冷冻干燥(FD)程序中的温度设定影响果蔬干制品的感官和营养品质。为获得蓝莓FD较优程序,本研究采用差示扫描量热法探究蓝莓热力学特性及玻璃化转变温度(Tg)的变化,采用低场核磁共振技术测定水分分布及含量变化,以收缩率、花青... 详细信息

不同真空冷冻干燥(FD)程序中的温度设定影响果蔬干制品的感官和营养品质。为获得蓝莓FD较优程序,本研究采用差示扫描量热法探究蓝莓热力学特性及玻璃化转变温度(Tg)的变化,采用低场核磁共振技术测定水分分布及含量变化,以收缩率、花青素含量和质构品质为指标,探究5种FD不同升温程序对蓝莓脆干燥特性和营养品质的影响。结果表明,超声处理后蓝莓共晶点、共熔点和Tg无显著变化;随着蓝莓含水率的降低,其Tg升高,蓝莓中的自由水先转换为不易流动水,随后不易流动水转换为自由水和结合水。FD不同程序设定下,蓝莓脆粒的收缩率、色泽、感官和营养品质变化显著(P<0.05)。程序2干燥后蓝莓脆粒的收缩率最小,程序1干燥后蓝莓脆粒的脆性最大,程序5干燥后蓝莓硬度最大;程序4干燥后蓝莓△E值最大,程序1干燥后蓝莓脆粒的维生素C(Vc)含量最高、抗氧化活性较高。综合考虑,确定较优FD程序为程序2:0℃(2 h)→5℃(2 h)→10℃(2 h)→20℃(2 h)→30℃(2 h)→40℃(2 h)→50℃(12 h)。本研究结果为蓝莓脆产品开发提供了理论基础。

关键词：蓝莓真空冷冻干燥超声共晶点升温程序

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发芽对不同品种糙米γ-氨基丁酸及酚类物质累积的调控作用

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食品与发酵工业 2024年第15期50卷 272-280页

作者：汪昱柯王冕王晓晴宋世钰谢翀蔡敬敬胡标林杨润强南京农业大学食品科学技术学院全谷物食品工程研究中心江苏南京210095 江苏百斯特鲜食有限公司江苏淮安223200 江西省农业科学院水稻研究所江西南昌330299

发芽可激活种子的内源酶,增加γ-氨基丁酸(γ-aminobutyric acid,GABA)、酚酸等功能成分含量。该研究以粤秀优197、万象优197、泰丰优197等12个糙米品种为研究对象,研究30℃黑暗催芽36 h后GABA与酚类物质合成情况,分别筛选GABA与酚类物... 详细信息

发芽可激活种子的内源酶,增加γ-氨基丁酸(γ-aminobutyric acid,GABA)、酚酸等功能成分含量。该研究以粤秀优197、万象优197、泰丰优197等12个糙米品种为研究对象,研究30℃黑暗催芽36 h后GABA与酚类物质合成情况,分别筛选GABA与酚类物质含量上升的品种,探究其相关酶活力的变化。结果表明,各品种糙米经发芽后GABA和总酚含量变化不同。万象优197、泰丰优197、万象优111、上两优798和莲玉香2号5个品种糙米的总酚含量较对照显著增加25.97%~178.53%,其中上两优798提高幅度最大。对香豆酸和丁香酸是糙米中主要的酚酸类型,分别占糙米总酚酸的12.37%~43.31%和21.80%~62.08%;然而,不同品种的发芽糙米中酚酸的组成及其含量存在差异。萌发提高了糙米中谷氨酸脱羧酶(glutamic acid decarboxylase,GAD)、苯丙氨酸解氨酶(phenylalanine aminolyase,PAL)、肉桂酸-4-羟化酶(cinnamic acid-4-hydroxylase,C4H)、4-香豆酸辅酶A连接酶(4-coumarate coenzyme A ligase,4CL)等活力,从而实现了GABA和酚类化合物的累积。该研究结果为开发富含生物活性物质的发芽糙米提供数据支撑。

关键词：糙米发芽酚类物质 γ-氨基丁酸

Optimizing techno-functionality of germinated whole wheat flour steamed bread via glucose oxidase(Gox)and pentosanase(Pn)enzyme innovation

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Grain & Oil Science and Technology 2023年第4期6卷 219-226页

作者： Muhammad Bilal Yining Zhang Dandan Li Chong Xie runqiang yang Zhenxin Gu Dong Jiang Pei Wang College of Food Science and Technology Whole Grain Food Engineering Research CenterNanjing Agricultural UniversityNanjingJiangsu 210095China National Technique Innovation Center for Regional Wheat Production/Key Laboratory of Crop Physiology Ecologyand ManagementMinistry of Agriculture/National Engineering and Technology Center for Information AgricultureNanjing Agricultural UniversityNanjingJiangsu 210095China The Sanya Institute of Nanjing Agricultural University Sanya 572024China

Germination,a powerful biofortification technique,holds immense potential in bolstering the micronutrient profile of essential staple grains,thereby paving the way for optimal nutritional *** primary goal of this study was to improve the technological functionality of germinated wheat flour by incorporating pentosanase(Pn)and glucose oxidase(Gox)enzymes,with particular emphasis on the evolutionary changes in its *** inclusion of Gox did not produce any substantial impact on the volumetric characteristics of the steamed *** incorporation of Pn and Gox has been seen to enhance the overall excellence of steamed bread by optimizing loaf volume and textural characteristics while also improving the thermal stability of the *** existence of two endothermic peaks could be attributed to bound water or alterations in the granules within the starch crystallization *** Pn and Gox reduced and increased the formation and stability time of the dough,respectively.A certain ratio was employed to assess alternations in the crystallinity of starch granules over a limited *** steaming,a significant decrease in IR1047/1022 was observed,indicating that the elevated temperature partially disrupted the internal starch crystal structure,leading to a gelatinization reaction with *** ratio of tensile resistance(R)and elongation(E)of dough increased significantly compared to the *** results obtained from this study indicate that the simultaneous inclusion of enzymes(Pn+Gox)holds significant promise for expanding the technological functionality of germinated wheat flour dough and improving the quality attributes of steamed bread.

关键词： Germinated wheat Steamed bread Enzymes Rheology Starch crystals Techno-functionality

An impact sensitivity assessment method of spacecraft based on virtual exterior wall

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Defence Technology（防务技术） 2024年第1期31卷 142-157页

作者： runqiang Chi Yuyan Liu Diqi Hu Baojun Pang Hypervelocity Impact Research Center Harbin Institute Of TechnologyHarbin150080China

The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit *** impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational *** method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the *** Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh *** influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and *** results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the *** PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size *** relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft.

关键词： Sensitivity OD/M Spacecraft Virtual exterior wall

Space debris environment engineering model 2019:Algorithms improvement and comparison with ORDEM 3.1 and MASTER-8

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Chinese Journal of Aeronautics 2024年第5期37卷 392-409页

作者： Yuyan LIU runqiang CHI Baojun PANG HU Diqi Wuxiong CAO Dongfang WANG School of Astronautics Harbin Institute of TechnologyHarbin 150001China College of Safety Science&Engineering Civil Aviation University of ChinaTianjin 300300China

As an essential tool for realistic description of the current or future debris environment,the Space Debris Environment Engineering Model(SDEEM)has been developed to provide support for risk assessment of *** contrast with SDEEM2015,SDEEM2019,the latest version,extends the orbital range from the Low Earth Orbit(LEO)to Geosynchronous Orbit(GEO)for the years *** this paper,improved modeling algorithms used by SDEEM2019 in propagating simulation,spatial density distribution,and spacecraft flux evaluation are *** debris fluxes of SDEEM2019 are compared with those of three typical models,i.e.,SDEEM2015,Orbital Debris Engineering Model 3.1(ORDEM 3.1),and Meteoroid and Space Debris Terrestrial Environment Reference(MASTER-8),in terms of two assessment *** orbital cases,including the Geostationary Transfer Orbit(GTO),Sun-Synchronous Orbit(SSO)and International Space Station(ISS)orbit,are selected for the spacecraft assessment mode,and the LEO region is selected for the spatial density assessment *** analysis indicates that compared with previous algorithms,the variable step-size orbital propagating algorithm based on semi-major axis control is more precise,the spatial density algorithm based on the second zonal harmonic of the non-spherical Earth gravity(J_(2))is more applicable,and the result of the position-centered spacecraft flux algorithm is more *** comparison shows that SDEEM2019 and MASTER-8 have consistent trends due to similar modeling processes,while the differences between SDEEM2019 and ORDEM 3.1 are mainly caused by different modeling approaches for uncatalogued debris.

关键词： SDEEM2019 Space debris propagating algorithm Spatial density algorithm ORDEM 3.1 MASTER-8

Red light enhances folate accumulation in wheat seedlings

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2021年第11期22卷 906-916页

作者： Jianwei CHANG Chong XIE Pei WANG Zhenxin GU Yongbin HAN runqiang yang College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China

Red,white,blue,green,and yellow lights were applied to investigate their effects on folate accumulation in wheat *** different lights,especially red light,significantly increased the total folate *** folate showed maximum accumulation under 30μmol/(m2·s)of red light,with an increase of 24%compared with the control(darkness).5-Methyltetrahydrofolate(5-CH3-THF)was the dominant folate component,and was significantly increased by red light *** addition,under red light,the folate content of leaves was higher and more sensitive to light than that of endosperm or *** light up-regulated the expression of guanosine triphosphate(GTP)cyclohydrolase 1(GCH1)and aminodeoxychorismate synthase(ADCS),enhanced the activity of GCH1 and ADCS,and increased the content of precursors of folate synthesis,including pterin and p-aminobenzoic acid(p ABA).Hence,the increased folate accumulation promoted by light could be attributed to the increased content of folate synthesis precursors,the activity of key enzymes,and related gene expression。

关键词： Wheat Red light Light intensity Folate accumulation

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： yang yang Guanxin Yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Overview of radar detection methods for low altitude targets in marine environments

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Journal of Systems Engineering and Electronics 2024年第1期35卷 1-13页

作者： yang Yong yang Boyu School of Electronic Science National University of Defense TechnologyChangsha 410073China

In this paper,a comprehensive overview of radar detection methods for low-altitude targets in maritime environments is presented,focusing on the challenges posed by sea clutter and multipath *** performance of the radar detection methods under sea clutter,multipath,and combined conditions is categorized and summarized,and future research directions are outlined to enhance radar detection performance for low-altitude targets in maritime environments.

关键词： radar sea clutter multipath scattering detection low altitude target