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Expert Experience and Data-Driven Based Hybrid Fault Diagnosis for High-SpeedWire Rod Finishing Mills 被引量:1
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作者 Cunsong Wang Ningze Tang +3 位作者 Quanling Zhang Lixin Gao Haichen Yin Hao Peng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1827-1847,共21页
The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault lo... The reliable operation of high-speed wire rod finishing mills is crucial in the steel production enterprise.As complex system-level equipment,it is difficult for high-speed wire rod finishing mills to realize fault location and real-time monitoring.To solve the above problems,an expert experience and data-driven-based hybrid fault diagnosis method for high-speed wire rod finishing mills is proposed in this paper.First,based on its mechanical structure,time and frequency domain analysis are improved in fault feature extraction.The approach of combining virtual value,peak value with kurtosis value index,is adopted in time domain analysis.Speed adjustment and side frequency analysis are proposed in frequency domain analysis to obtain accurate component characteristic frequency and its corresponding sideband.Then,according to time and frequency domain characteristics,fault location based on expert experience is proposed to get an accurate fault result.Finally,the proposed method is implemented in the equipment intelligent diagnosis system.By taking an equipment fault on site,for example,the effectiveness of the proposed method is illustrated in the system. 展开更多
关键词 High-speed wire rod finishing mills expert experience DATA-DRIVEN fault diagnosis
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Prevalence of Noise-Induced Hearing Loss Related to the Mills in the Markets of the Municipality of Parakou in 2021
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作者 Fatiou Alabi Bouraïma Cocouvi Bruno Ametonou +5 位作者 Ulrich Bidossèssi Vodouhe François Avakoudjo Jorelle Wafo Marius Claude Flatin Spéro H. R. Hounkpatin Wassi Adjibabi 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第1期1-10,共10页
Introduction: Noise is the second leading cause of hearing loss in adults after presbycusis. The objective of this work was to study hearing loss induced by the noise of mills in the markets of Parakou. Methods: This ... Introduction: Noise is the second leading cause of hearing loss in adults after presbycusis. The objective of this work was to study hearing loss induced by the noise of mills in the markets of Parakou. Methods: This was a descriptive and analytical cross-sectional study, conducted from February 3 to June 3, 2021 in the markets of Parakou. It concerned millers and sellers located within a 5 meter radius around the mills and among whom pure-tone audiometry was performed to detect a hearing loss. Subjects with no particular medical health history, under 55 years of age and having been working in these markets since more than 12 months, were included. Results: In this study, 103 subjects were selected, including 43 millers and 61 sellers. Their average age was 29 ± 13 years. The sex ratio was 0.49. The average length of service in the profession was 8 years with the extremes of 3 months and 47 years. They were exposed to noise on average 10 hours per day and 6 days a week. The average duration of weekly noise exposure was 23 h 28 min ± 13 h 32 min with the extremes of 5 h 00 min and 52 h 30 min. The average level of noise exposure was 90 dB with the extremes of 72 and 110 dB. 24 subjects reported symptoms related to noise such as headache, tinnitus, and hearing loss, with respective proportions of 22.33%, 20.39% and 06.80%. The prevalence of noise-related hearing loss was 26.21% (n = 27/103). Subjects with a notch at 4000 Hz and normal Average Hearing Loss (AHL) (20.39%) had a seven-time greater risk of developing noise-induced hearing loss (OR = 6.58;95% CI [2.54 - 18.8], p Conclusion: Hearing loss related to the noise of mills affected both millers and sellers near the mills in markets, hence the importance of regulating mills. 展开更多
关键词 Noise-Induced Hearing Loss mills MARKETS Parakou
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一类由Hermitian Yang-Mills度量导出的半线性偏微分方程
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作者 李宇萱 周武斌 《数学杂志》 2023年第4期283-287,共5页
本文研究了由一类Hermitian Yang-Mills度量的极限行为所导出的半线性方程的边值问题与全局解的径向对称性质.使用极大值原理与Leray-Schhauder不动点定理,我们得到了这个方程在R^(2)平面中全局C2解的径向对称性与这个方程的Dirichlet... 本文研究了由一类Hermitian Yang-Mills度量的极限行为所导出的半线性方程的边值问题与全局解的径向对称性质.使用极大值原理与Leray-Schhauder不动点定理,我们得到了这个方程在R^(2)平面中全局C2解的径向对称性与这个方程的Dirichlet问题在任意有界区域内C^(2,α)解的存在性. 展开更多
关键词 Hermitian yang-mills度量 C^(k)-估计 边值问题
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2n维空间中的广义自对偶Yang-Mills方程的达布变换 被引量:1
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作者 沈守枫 于水猛 +1 位作者 李春霞 金永阳 《数学物理学报(A辑)》 CSCD 北大核心 2015年第3期478-486,共9页
从带负幂次谱参数的谱问题出发,构造了一类广义自对偶Yang-Mills方程.这类方程包括若干著名的Lax可积方程,如Takasaki情形、Belavin-Zakharov情形、AblowitzChakravarty-Takhtajall情形和Ma情形.进而建立了这类方程的达布变换的精确表达式.
关键词 达布变换 自对偶yang-mills方程 Lax可积 谱问题
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A topological way of finding solutions to the Yang–Mills equation
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作者 Jun Nian Yachao Qian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2020年第8期87-95,共9页
We propose a systematic way of finding solutions to the classical Yang–Mills equation with nontrivial topology. This approach is based on one of the Wightman axioms for quantum field theory, which is referred to as t... We propose a systematic way of finding solutions to the classical Yang–Mills equation with nontrivial topology. This approach is based on one of the Wightman axioms for quantum field theory, which is referred to as the form invariance condition in this paper. For a given gauge group and a spacetime with certain isometries, thanks to this axiom that imposes strong constraints on the general ansatz, a systematic way of solving the Yang–Mills equation can be obtained in both flat and curved spacetimes. In order to demonstrate this method, we recover various known solutions as special cases, as well as producing new solutions not previously reported in the literature. 展开更多
关键词 yang–mills theory form invariance curved space exact solutions Wu-yang monopole INSTANTON
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规范固定Yang-Mills热流的能量不等式与Bochner估计
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作者 姚纯青 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2007年第3期28-32,共5页
通过推导曲率及其高阶导数的演化式,得到了规范固定Yang-Mills热流的能量不等式和Bochner估计.
关键词 规范固定 yangmills热流 能量不等式 Bochner估计
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De Sitter空间中的Yang-Mills场
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作者 沈学文 丁舜扬 徐慧群 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2008年第3期502-504,共3页
将Bourguigonon和Lawson的球面上的孤立性现象推广到de Sitter空间中的n维紧致类空子流形上,得到了当紧致类空子流形满足某一条件时,则Yang-Mills场消失.还运用整体拼挤估计,证得Mn上任意的Yang-Mills联络是平坦的.
关键词 yang-mills 类空子流形 孤立性 平坦联络
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球面中紧致子流形上Yang-Mills场的不稳定性和孤立性
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作者 蔡开仁 徐慧群 《工程数学学报》 CSCD 北大核心 2005年第5期898-902,共5页
设M是球面Sn+p中的n维紧致定向的浸入子流形,则存在一个仅与M的第二基本形式长度平方和平均曲率有关的正常数A,当n>4+A时,M上不存在非平凡的弱稳定的Yang-Mills场。从而推广了Simons的关于球面Sn是Yang-Mills不稳定的经典定理。本文... 设M是球面Sn+p中的n维紧致定向的浸入子流形,则存在一个仅与M的第二基本形式长度平方和平均曲率有关的正常数A,当n>4+A时,M上不存在非平凡的弱稳定的Yang-Mills场。从而推广了Simons的关于球面Sn是Yang-Mills不稳定的经典定理。本文也证明了球面的紧致子流形上的Yang-Mills场,存在空隙性现象。 展开更多
关键词 yang-mills 子流形 不稳定性 孤立性
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整体Pinching引理及其在子流形的几何、调和映射和Yang-Mills场中的应用(英文)
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作者 周振荣 陈群 《数学进展》 CSCD 北大核心 2003年第3期319-326,共8页
本文建立了两个解析引理,并将它们应用于子流形的几何、调和映射以及Yang-Mills场理论,从而获得了关于这些对象的几个整体Pinching结果。
关键词 整体Pinching引理 紧Kaehler子流形 “流形的几何” 调和映射 yang-mills 黎曼流形
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De Sitter空间中紧致类空子流形上Yang-Mills场的不稳定性
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作者 蔡开仁 徐慧群 《杭州师范学院学报(自然科学版)》 CAS 2005年第4期251-255,共5页
设M是deSitter空间Snp+p(1)中的n维紧致类空子流形,则存在一个仅与M的第二基本形式长度平方σ和平均曲率有关的正常数A,当n>4+A时,M上不存在非平凡的弱稳定的Yang-Mills场.从而推广了Simons关于球面Sn是Yang-Mills不稳定的经典定理.
关键词 yang-mills 子流形 不稳定性 de SITTER空间
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p-Yang-Mills泛函的变分公式
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作者 蔡开仁 马加佳 《杭州师范学院学报(自然科学版)》 CAS 2006年第1期1-4,共4页
推导了p-Yang-Mills泛函的第一和第二变分公式,并证明了关于p-Yang-Mills泛函的一个不稳定性定理,即球面Sn,(n>2p≥4)上平行的p-Yang-Mills场是不稳定的.
关键词 P-yang-mills泛函 第一变分 第二变分 稳定性
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Yang-Mills流演化问题奇点集的估计(英文)
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作者 沈自飞 《数学进展》 CSCD 北大核心 1999年第5期427-430,共4页
给出了Yang-Mills流演化问题奇点集的一个估计.
关键词 黎曼流形 yang-mills 奇点集 估计 演化问题
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Yang-Mills理论、维度正规化及其它
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作者 张端明 黄明涛 《云南民族学院学报(自然科学版)》 CAS 2001年第1期253-258,共6页
首先介绍了 1999年度诺贝尔物理学奖得主 ,胡夫特和维尔特曼的维度正规化方案 .然后简要阐述Yang -Mills理论的基本思想、发展概况 ,尤其是其中的重整化问题和真空对称性自发破缺机制 ,评述了作为 2 0世纪量子论发展的最高阶段———量... 首先介绍了 1999年度诺贝尔物理学奖得主 ,胡夫特和维尔特曼的维度正规化方案 .然后简要阐述Yang -Mills理论的基本思想、发展概况 ,尤其是其中的重整化问题和真空对称性自发破缺机制 ,评述了作为 2 0世纪量子论发展的最高阶段———量子化的Yang -Mills理论 ,对于整个物理学 ,尤其是基本粒子的基本相互作用理论的巨大贡献 .最后展望了 2 1世纪物理学发展的趋向 . 展开更多
关键词 yang-mills理论 维度正规化 重整化 弱电相互作用 量子色动力学 非阿贝尔局域规范理论 量子论 真空对称性自发破缺机制
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Some Evolution Hierarchies Derived from Self-dual Yang-Mills Equations 被引量:8
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作者 张玉峰 韩耀宗 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期856-872,共17页
We develop in this paper a new method to construct two explicit Lie algebras E and F.By using aloop algebra E of the Lie algebra E and the reduced self-dual Yang-Mills equations,we obtain an expanding integrablemodel ... We develop in this paper a new method to construct two explicit Lie algebras E and F.By using aloop algebra E of the Lie algebra E and the reduced self-dual Yang-Mills equations,we obtain an expanding integrablemodel of the Giachetti-Johnson (GJ)hierarchy whose Hamiltonian structure can also be derived by using the traceidentity.This provides a much simplier construction method in comparing with the tedious variational identity approach.Furthermore,the nonlinear integrable coupling of the GJ hierarchy is readily obtained by introducing the Lie algebra g_N.As an application,we apply the loop algebra E of the Lie algebra E to obtain a kind of expanding integrable model ofthe Kaup-Newell (KN)hierarchy which,consisting of two arbitrary parameters a and f3,can be reduced to two nonlinearevolution equations.In addition,we use a loop algebra F of the Lie algebra F to obtain an expanding integrable model ofthe BT hierarchy whose Hamiltonian structure is the same as using the trace identity.Finally,we deduce five integrablesystems in R3 based on the self-dual Yang-Mills equations,which include Poisson structures,irregular lines,and thereduced equations. 展开更多
关键词 演化方程 HAMILTON结构 扩展可积模型 LOOP代数 演变 层次结构 线性代数 泊松结构
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Generation of Nonlinear Evolution Equations by Reductions of the Self-Dual Yang–Mills Equations 被引量:4
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作者 张玉峰 Hon-Wah Tam 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第2期203-206,共4页
With the help of some reductions of the self-dual Yang Mills(briefly written as sdYM) equations, we introduce a Lax pair whose compatibility condition leads to a set of(2 + 1)-dimensional equations. Its first reductio... With the help of some reductions of the self-dual Yang Mills(briefly written as sdYM) equations, we introduce a Lax pair whose compatibility condition leads to a set of(2 + 1)-dimensional equations. Its first reduction gives rise to a generalized variable-coefficient Burgers equation with a forced term. Furthermore, the Burgers equation again reduces to a forced Burgers equation with constant coefficients, the standard Burgers equation, the heat equation,the Fisher equation, and the Huxley equation, respectively. The second reduction generates a few new(2 + 1)-dimensional nonlinear integrable systems, in particular, obtains a kind of(2 + 1)-dimensional integrable couplings of a new(2 + 1)-dimensional integrable nonlinear equation. 展开更多
关键词 非线性发展方程 变系数BURGERS方程 自对偶 减排量 可积系统 热传导方程 非线性方程 LAX对
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Effects of Milling Methods on Rice Flour Properties and Rice Product Quality:A Review
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作者 TIAN Yu SUN Jing +7 位作者 LI Jiaxin WANG Aixia NIE Mengzi GONG Xue WANG Lili LIU Liya WANG Fengzhong TONG Litao 《Rice science》 SCIE CSCD 2024年第1期33-46,共14页
High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and qualit... High-quality rice flour is the foundation for the production of various rice-based products.Milling is an essential step in obtaining rice flour,during which significant changes occur in the physicochemical and quality characteristics of the flour.Although rice flour obtained through mainstream wet milling methods exhibits superior quality,low production efficiency and wastewater discharge limit the development of the industry.Dry milling,on the other hand,conserves water resources,but adversely affects flour performance due to excessive heat generation.As an emerging powder-making technique,semi-dry milling offers a promising solution by enhancing flour quality and reducing environmental impact.This is achieved by minimizing soaking time through hot air treatment while reducing mechanical energy consumption to reach saturated water absorption levels.However,continuous production remains a challenge.This comprehensive review summarizes the effects of various milling technologies on rice flour properties and product qualities.It also discusses key control indicators and technical considerations for rice flour processing equipment and processes. 展开更多
关键词 flour property milling equipment milling method rice flour rice product quality semi-dry milling
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Balanced Fracturing and Cold-welding of Magnesium during Ball Milling Assisted by Carbon Coating:Experimental and Molecular Dynamic Simulation
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作者 韩宗盈 DONG Hui +2 位作者 DING Guoyang ZHANG Jiale SONG Xiufang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期895-903,共9页
The lignite-derived carbon from self-protection pyrolysis was employed to balance the fracturing and cold-welding of magnesium during ball milling.Particle size analysis indicates that the introduction of lignite-deri... The lignite-derived carbon from self-protection pyrolysis was employed to balance the fracturing and cold-welding of magnesium during ball milling.Particle size analysis indicates that the introduction of lignite-derived carbon can effectively reduce the particle size of Mg while the introduction of graphite does no help.Besides,the effect of lignite-derived carbon on crystallite size reduction of Mg is also better than graphite.A moderate cold-welding phenomenon was observed after ball-milling Mg with the lignite-derived carbon,suggesting less Mg is wasted on the milling vials and balls.Molecular dynamic simulations reveal that the balanced fracturing and cold-welding of magnesium during ball milling is mainly attributed to the special structure of the lignite-derived carbon:graphitized short-range ordered stacking function as dry lubricant and irregular shape/sharp edge function as milling aid.The preliminary findings in current study are expected to offer implications for designing efficient Mg-based hydrogen storage materials. 展开更多
关键词 MAGNESIUM lignite-derived carbon cold-welding ball milling molecular dynamic
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Milling degree affects the fermentation properties of rice:perspectives from the composition of nutrients and gut microbiota via in vitro fermentation
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作者 Yu Zhang Fan Li +7 位作者 Shutong Pan Bing Bai Kai Huang Sen Li Hongwei Cao Tian Xie Jian Xie Xiao Guan 《Food Science and Human Wellness》 SCIE CSCD 2024年第3期1578-1588,共11页
Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represente... Fermentation substrates of rice with different milling degrees(MDs) were prepared and fermented with human feces to compare their fermentation properties and effects on gut microbiota.MD 0s,MD 5s and MD 60s represented brown rice,moderately-milled rice and white rice,respectively.After in vitro fermentation,the MD 5s group showed higher starch utilization,compared with the MD 0s and 60s groups evaluated by Fourier transform infrared spectrometer,and confocal laser scanning microscope.Effects of fermentation substrates of rice with different MDs on gut microbiota were evaluated by 16S rDNA sequencing.All the sample groups reduced the pH and produced short-chain fatty acids(SCFAs) and branched-chain fatty acids.The MD 5s group exhibited higher α-diversity than the MD 0s and 60s groups.Abundances of Phascolarctobacterium,Blautia and norank_f_Ruminococcaceae were higher in the MD 0s and 5s groups,compared with the MD 60s group.These bacteria were also positively correlated with the SCFAs production via Spearman correlation analysis.In vitro culture assay revealed that fermentation substrates of MD 0s and 5s promoted the growth of two probiotics(Akkermansia muciniphila and Bifidobacterium adolescentis).Our results showed that moderate milling might be an appropriate way to produce rice products with richer nutrients and better fermentation properties. 展开更多
关键词 Rice processing millING Whole grains Gut microbiota
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Improving hydrogen storage thermodynamics and kinetics of Ce-Mg-Ni-based alloy by mechanical milling with TiF_(3)
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作者 Hongwei Shang Wei Zhang +4 位作者 Xin Wei Yaqin Li Zeming Yuan Jun Li Yanghuan Zhang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1593-1607,共15页
Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not satisfactory.An efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocompo... Mg-based hydrides are too stable and the kinetics of hydrogen absorption and desorption is not satisfactory.An efficient way to improve these shortcomings is to employ reactive ball milling to synthesize the nanocomposite materials of Mg and additives.In this experiment,TiF_(3)was selected as an additive,and the mechanical milling method was employed to prepare the experimental alloys.The alloys used in this experiment were the as-cast Ce_(5)Mg_(85)Ni_(10),as-milled Ce_(5)Mg_(85)Ni_(10)and Ce_(5)Mg_(85)Ni_(10)+3 wt.%TiF3.The phase transformation,structural evolution,isothermal and non-isothermal hydrogenation and dehydrogenation performances of the alloys were inspected by XRD,SEM,TEM,Sievert apparatus,DSC and TGA.It revealed that nanocrystalline appeared in the as-milled samples.Compared with the as-cast alloy,ball milling made the particle dimension and grain size decrease dramatically and the defect density increase significantly.The addition of TiF_(3)made the surface of ball milling alloy particles markedly coarser and more irregular.Ball milling and adding TiF_(3)distinctly improved the activation and kinetics of the alloys.Moreover,ball milling along with TiF_(3)can decrease the onset dehydrogenation temperature of Mg-based hydrides and slightly ameliorate their thermodynamics. 展开更多
关键词 Mg-based hydrides TiF_(3) Ball milling THERMODYNAMICS KINETICS
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Distribution of antioxidants and phenolic compounds in flour milling fractions from hard red winter wheat
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作者 Lauren Renee Brewer Jittawan Kubola +1 位作者 Sirithon Siriamornpun Yong-Cheng Shi 《Grain & Oil Science and Technology》 CAS 2024年第2期71-78,共8页
Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not bee... Mature wheat kernels contain three main parts:endosperm,bran,and germ.Flour milling results in multiple streams that are chemically different;however,the distribution of antioxidants and phenolic compounds has not been well documented in terms of conventional milling by-product streams.In this study,multiple analytical methods were used to investigate antioxidant activity and phenolic compound compositions of hard red winter wheat(whole ground wheat),the parts of a wheat kernel(bran,flour,germ),and wheat by-product streams(mill feed,red dog,shorts)for the first time.For each mill stream,phenolic compounds(total,flavonoid,and anthocyanin contents)were determined and antioxidant activities were evaluated with 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical-scavenging activity,ferric reducing/antioxidant power(FRAP),and total antioxidant capacity assays.Significant differences(P<0.05)were observed in phenolic concentrations among fractions of bran,flour,and germ milled from the same kernels and noted that germ accounts for the majority of antioxidant properties,whereas bran contains a substantial portion of phenolic compounds and anthocyanins.Mill feed was high in phenolic content(5.29 mg FAE/g),total antioxidant capacity(866 mg/g),and antioxidant activity(up to 75% DPPH inhibition and 20.26μmol FeSO_(4)/g).The comprehensive information on distribution of antioxidants and phenolic compounds provides insights for future human consumption of commonly produced co-products from flour milling,and for selecting and using different milling fractions to make foods with improved nutritional properties. 展开更多
关键词 Wheat milling streams ANTIOXIDANTS Phenolic acids Flavonoid ANTHOCYANIN
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