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荞麦醋有机酸和多酚组成及其对牛肉保鲜效果研究

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中国调味品 2024年第7期49卷 10-16页

作者：沈西平马浩睿李林强陕西师范大学食品工程与营养科学学院西安710119

文章分析荞麦醋有机酸和多酚的组成并探讨其对牛肉的保鲜效果。荞麦经过酒精发酵与醋酸发酵制得荞麦醋;采用高效液相色谱(HPLC)分析其有机酸和酚类化合物组成,并用荞麦醋浸渍牛肉,测定牛肉冷藏(2~4℃)过程中(12,24,36,48,60 h)色泽、抗... 详细信息

文章分析荞麦醋有机酸和多酚的组成并探讨其对牛肉的保鲜效果。荞麦经过酒精发酵与醋酸发酵制得荞麦醋;采用高效液相色谱(HPLC)分析其有机酸和酚类化合物组成,并用荞麦醋浸渍牛肉,测定牛肉冷藏(2~4℃)过程中(12,24,36,48,60 h)色泽、抗氧化能力、挥发性盐基氮(TVB-N)含量、丙二醛含量、细菌总数和质构的变化。结果表明,荞麦醋中有6种有机酸,其中乙酸含量最高,为3.134 g/dL;9种酚类化合物,其中表儿茶素没食子酸酯含量最高,为50.535 mg/dL。荞麦醋浸渍牛肉在贮藏过程中(12~60 h)色泽、细菌总数、丙二醛含量和挥发性盐基氮含量显著低于对照组(P<0.05),抗氧化能力和质构特性显著高于对照组(P<0.05)。荞麦醋含有多种有机酸和多酚类化合物,能有效改善冷藏牛肉的保鲜效果。

关键词：荞麦醋有机酸多酚牛肉保鲜

Precise determination of the top-quark on-shell mass Mt via its scale-invariant perturbative relation to the top-quark MS mass m_(t)(m_(t))

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Chinese Physics C 2024年第5期48卷 180-193页

作者：黄旭东吴兴刚郑绪昌闫江吴知非马鸿浩 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Department of Physics Chongqing Key Laboratory for Strongly Coupled PhysicsChongqing UniversityChongqing 401331China Department of Physics Guangxi Normal UniversityGuilin 541004China

The principle of maximum conformality(PMC)provides a systematic approach to solve the conventional renormalization scheme and scale ***-fixed predictions of physical observables using the PMC are independent of the choice of renormalization scheme–a key requirement for renormalization group *** this paper,we derive new degeneracy relations based on the renormalization group equations that involve both the usualβ-function and the quark mass anomalous dimensionγ*** new degeneracy relations enable improved PMC scale-setting procedures for correct magnitudes of the strong coupling constant and MS¯-running quark mass to be determined *** using these improved PMC scale-setting procedures,the renormalization scale dependence of the MS¯-on-shell quark mass relation can be eliminated ***,the top-quark on-shell(or MS¯)mass can be determined without conventional renormalization scale *** the top-quark MS¯mass m¯t(m¯t)=162.5+2.1−1.5 GeV as the input,we obtain Mt≃172.41+2.21−1.57 ***,the uncertainties arise from errors combined with those fromΔαs(MZ)and the approximate uncertainty resulting from the uncalculated five-loop terms predicted through the Padéapproximation approach.

关键词： perturbative QCD top quark mass renormalization

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Metric of States

Communications in Theoretical Physics 2008年第11期50卷 1069-1070页

作者： ma Zhi-hao Department of mathematics Shanghai Jiao Tong University Shanghai 200240 China

Metric of quantum states plays an important role in quantum information theory. In this letter, we find the deep connection between quantum logic theory and quantum information theory. Using the method of quantum logi... 详细信息

关键词： state density operator metric fidelity quantum information quantum logic

Crossover Phenomena in Detrended Fluctuation Analysis Used in Financial markets

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Communications in Theoretical Physics 2009年第2期51卷 358-362页

作者： ma Shi-hao College of Physical Science and Technology Huazhong Normal University Wuhan 430079 China

A systematic analysis of Shanghai and Japan stock indices for the period of Jan. 1984 to Dec. 2005 is performed. After stationarity is verified by ADF （Augmented Dickey-Fuller） test, the power spectrum of the data exhibits a power law decay as a whole characterized by 1/f^β processes with possible long range correlations. Subsequently, by using the method of detrended fluctuation analysis （DFA） of the general volatility in the stock markets, we find that the long-range correlations are occurred among the return series and the crossover phenomena exhibit in the results ***, Shanghai stock market shows long-range correlations in short time scale and shows short-range correlations in long time scale. Whereas, for Japan stock market, the data behaves oppositely absolutely. Last, we compare the varying of scale exponent in large volatility between two stock markets. All results obtained may indicate the possibility of characteristic of multifractal scaling behavior of the financial markets.

关键词： financial market crossover phenomena detrended fluctuation analysis

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电机轴承润滑油膜电容计算与试验研究

轴承 2024年第5期 131-137页

作者：马浩李伟李继伟王永强西安中车永电捷力风能有限公司西安710016 轨道交通牵引电机山西省重点实验室山西永济044500

为获得轴承运行条件下油膜的电容参数,基于有限元软件建立包含轴承内圈、滚动体、保持架、外圈、润滑脂的计算模型,分析轴承在运行条件下的电场分布,并计算轴承各导体的电荷量,求得多导体轴承系统的电容矩阵,从而求得在该条件下6016深... 详细信息

为获得轴承运行条件下油膜的电容参数,基于有限元软件建立包含轴承内圈、滚动体、保持架、外圈、润滑脂的计算模型,分析轴承在运行条件下的电场分布,并计算轴承各导体的电荷量,求得多导体轴承系统的电容矩阵,从而求得在该条件下6016深沟球轴承的油膜电容为0.169 nF。根据轴承油膜电容产生的原理,搭建轴承油膜电容试验台,得到6016深沟球轴承油膜电容的测试值为0.194 nF,与其他计算方法相比,文中方法计算值与测试值误差最小,确认了该方法的准确性。

关键词：滚动轴承牵引电动机油膜电容赫兹接触有限元分析

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弯曲参数对304不锈钢管材大曲率无芯弯曲成形性的影响

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塑性工程学报 2024年第6期31卷 34-42页

作者：苟毓俊李永勋马森浩宋佳茹陈建勋太原科技大学车辆与交通工程学院山西太原030024 智慧交通山西省实验室山西太原030024 太原科技大学材料科学与工程学院山西太原030024

针对管材无芯弯曲多缺陷耦合的成形问题,以管材壁厚变化率及截面短轴变化率作为成形指标,在不同弯曲参数下进行304不锈钢管材大曲率无芯弯曲试验,结合硬度测试及微观组织表征,研究了弯曲参数对弯曲成形及微观组织演变的影响规律。结果表... 详细信息

针对管材无芯弯曲多缺陷耦合的成形问题,以管材壁厚变化率及截面短轴变化率作为成形指标,在不同弯曲参数下进行304不锈钢管材大曲率无芯弯曲试验,结合硬度测试及微观组织表征,研究了弯曲参数对弯曲成形及微观组织演变的影响规律。结果表明:随着弯曲速度、弯曲角度及相对管径的增大,壁厚变化率呈增加趋势,且壁厚增厚率始终大于壁厚减薄率,同时,弯管截面畸变程度加剧。在各弯曲参数下,管材弯曲内外侧均发生奥氏体向马氏体转变,马氏体组织含量及硬度与壁厚变化率呈正相关关系,中性层几乎不存在马氏体。通过选择合适的工艺,最终弯制出相对弯曲半径为1.4的合格弯管。

关键词：薄壁管材大曲率无芯弯曲成形性微观组织

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长大断面隧道软岩复合式衬砌支护施工技术

价值工程 2024年第11期43卷 86-89页

作者：马世豪韩磊涛中交路桥建设有限公司北京100000

支护施工对隧道建设具有举足轻重的作用,在现有隧道施工中受其自身岩性等级影响,支护体系以及支护参数的选择存在一定难度,尤其在长大断面隧道软岩支护施工中,若支护参数和施工方案与隧道实际围岩不匹配,可能出现耐久性不足的安全隐患问... 详细信息

支护施工对隧道建设具有举足轻重的作用,在现有隧道施工中受其自身岩性等级影响,支护体系以及支护参数的选择存在一定难度,尤其在长大断面隧道软岩支护施工中,若支护参数和施工方案与隧道实际围岩不匹配,可能出现耐久性不足的安全隐患问题,为此,研究长大断面隧道软岩复合式衬砌支护施工技术。以某高速公路建设工程中的隧道为研究对象,在分析其地质条件后,针对Ⅳ、Ⅴ级别围岩设计复合式衬砌支护施工方法,在共同作用模型中获取断面隧道围岩荷载,基于围岩荷载确定复合式衬砌支护参数;根据守恒原理设计Ⅳ、Ⅴ级别围岩复合式衬砌支护施工工序。结果表明:分别在隧道断面的拱顶、拱腰和拱脚布置监测点,所研究方法应用下各测点的位移情况小于6mm,具有应用价值。

关键词：长大断面隧道软岩地质复合式衬砌支护施工技术

Improving interlaminar fracture toughness of flax fiber/epoxy composites with chopped flax yarn interleaving

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Science China(Technological Sciences) 2015年第10期58卷 1745-1752页

作者： LI Yan WANG Di ma hao School of Aerospace Engineering and Applied Mechanics Tongji University Key Laboratory of Advanced Civil Engineering materials Ministry of Education Tongji University

In this research, unidirectional flax fabrics reinforced epoxy laminates were intedeaved with randomly oriented chopped flax yarns at various yarn lengths and contents. Mode I interlaminar fracture toughness of the laminates was evaluated via Double Cantilever Beam （DCB） tests. The results showed that Mode I interlaminar fracture toughness increased with the introduction of the chopped yarns. With moderate yarn length and content, the best toughening effect （31% improvement in Mode I inter- laminar fracture toughness） was achieved. It was observed with the aid of Scanning Electronic Microscopy （SEM） that the in- troduction of the chopped yarns resulted in more tortuous in-plane crack propagation paths as well as the ＂trans-layer＂ phe- nomenon and fiber bridging effect of both the unidirectional yams and the chopped yams. These hindered the growth of the crack and led to more energy dissipation during delamination progress. Excessive yam length or content would induce unstable crack propagation and thus weakened the toughening improvement. No remarkable change was found in the tensile properties and the Charpy impact strength for the interleaved laminates, which indicated that this interleaving method was effective on interlaminar toughening without sacrificing the comprehensive mechanical properties of the laminates.

关键词： natural fiber reinforced composites interlaminar fracture toughness interlaminar toughening interleaving fiberbridging trans-layer effect

Construction of Authentication Codes with Double Arbiters over Symplectic Geometry

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Acta mathematicae Applicatae Sinica 2015年第4期31卷 1141-1152页

作者： Shang-di CHEN hao ma College of Science Civil Aviation University of China

In a common authentication code with arbitration, the dishonest arbiter may make a threat to the security of authentication system. In this paper, an authentication code with double arbiters over symplectic geometry is constructed, and the relevant parameters and the probabilities of successful attacks are calculated. The model not only prevents deception from the opponent and members of the system, but also effectively limits the attacks of single arbiter. Moreover, the collusion attacks from arbiters and participators are difficult to succeed.

关键词： authentication code double arbiters symplectic geometry