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钴基非晶合金的穆斯堡尔研究

核技术 1985年第1期 14-16+24-72页

作者：许裕生 m.ghafari H.P.Klein U.Gonser 苏州大学西德萨尔大学

非晶合金可以用不同的方法制备,本文所论及的金属-类金属非晶合金是用熔融态合金快速淬冷来制备的。为了研究非晶合金Co;Fe;B;m;（其中m=Ge、Si、C）的结构和热性质,我们用穆斯堡尔谱仪和示差热扫描仪（简称DSC仪）进行测量分析。

关键词：钴基非晶合金穆斯堡尔谱仪示差热扫描仪

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钴基非晶合金的穆斯堡尔谱研究

核技术 1984年第4期 24-24页

作者：许裕生 m.ghafari H.P.Klein U.Gonser 苏州大学 Jnivcrsitt des Saarlands Fed. Rep. Germany

用穆斯堡尔谱仪和DSC仪对钴基非晶Co74.5 57F0.5-B25-xmx合金进行测量分析。测量了类金属原子对平均超精细场的影响,讨论了钴基和铁基非晶合金的居里温度对类金属原子的依赖关系。在使用DSC仪测量中,观

关键词：非晶合金 CoDSC测量居里温度穆斯堡尔谱

Experimental and Numerical Study of Structural Identification Using Non-Linear Resonant Decay method

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Sound & Vibration 2019年第3期53卷 75-95页

作者： mehdi Sarmast Hamed ghafari Jan R.Wright Kennesaw State University Department of Mechanical EngineeringMD 9075840 Polytechnic Lane MariettaGA 30060USA malek Ashtar University of Technology Department of Aerospace EngineeringLavizanTehran 15875Iran School of mechanical Aerospace and Civil EngineeringUniversity of ManchesterManchester M139PLUK

One of the practical approaches in identifying structures is the non-linear resonant decay method which identifies a non-linear dynamic system utilizing a model based on linear modal space containing the underlying linear system and a small number of extra terms that exhibit the non-linear *** this paper,the method is illustrated in a simulated system and an experimental *** main objective of the non-linear resonant decay method is to identify the non-linear dynamic systems based on the use of a multi-shaker excitation using appropriated excitation which is obtained from the force appropriation *** experimental application of the method is indicated to provide suitable estimates of modal parameters for the identification of non-linear models of structures.

关键词： Non-linear modal identification non-linear dynamic system non-linear resonant decay method force appropriation approach

Comparative Study of the Antioxidant Activity of Two Popular Green Tea Beverages Available in the Local market of Saudi Arabia

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Natural Science 2016年第6期8卷 227-234页

作者： Ulfat m. Omar Ayat m. Shorbaji Entesar m. Arrait Tasneem D. Al Agha Hala F. Al-marzouki Huda A. Al Doghaither Ayat B. Al-ghafari Department of Biochemistry Faculty of Science King Abdulaziz University Jeddah KSA

Antioxidants have numerous applications due to their multiple roles in diminishing harmful effects of oxidative stress. The objective of this work was to highlight the importance of green tea by evaluating the antioxidant activity of the most popular green tea brands in Saudi Arabia, Lipton and Rabea. To our knowledge, no studies have so far been done to estimate the antioxidant activity of these brands. To determine the antioxidant activities of these two brands, 10 mg/ml of each brand was extracted and their total phenolic content (TPC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, hydrogen peroxide scavenging activity, ferric reducing power and ferrous ion chelating effect were measured. The TPC of Lipton tea was 678.7 υg of gallic acid equivalents (GAE)/10mg, whereas in Rabea tea, the TPC was 647.1 υg GAE/10mg. The presence study indicated that there were no significant differences in total phenolic contents and the percentage inhibition as shown in DPPH and H2O2 assays among Lipton and Rabea green teas. moreover, it was found that all assays have exhibited high antioxidant activity in both green teas. In conclusion, our study showed evidence for evenness and stability of the antioxidant activity of the two commercial green teas available in the markets of Saudi Arabia. Continued researches are needed to further the current knowledge on the health-promoting effects of this popular beverage using different supplements by different mechanisms.

关键词： Green Tea Polyphenols Antioxidants Radical Scavenging Activity Total Phenolic Content

Phenolic Contents and Antioxidant Activities of Green Tea with and without Lemon

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Natural Science 2016年第6期8卷 247-255页

作者： Ayat B. Al-ghafari Ayat m. Shorbaji Lamya A. AL-Sarori Eman O. Baduwailan Aisha A. Basaar Huda A. Al Doghaither Hala F. Al-marzouki Ulfat m. Omar Department of Biochemistry Faculty of Science King Abdulaziz University Jeddah KSA

Tea is the most widely consumed beverage throughout the world, after water and is considered as a good antioxidant nutrient against free radical reactions. Lemons are citrus fruits that are very common in many parts of the world and are well known for their health benefits. In this study, different assays were used to evaluate total phenolic content and antioxidant activities of green tea with and without lemon. Our results showed that green tea with lemon has higher phenolic content, stronger reducing power than green tea without lemon;and exhibits a significant inhibition of 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide (H2O2). However, both samples exhibited high ferrous chelating activity with no significant difference among each other indicating a good antioxidant potential for both. This is a comparative study between green tea and green tea supplemented with lemon. The study contributes to a better understanding about how the addition of supplements like lemon might influence the antioxidant activity of tea.

关键词： Antioxidant Activity Green Tea Lemon metal Chelation Phenolic Compounds Radical Scavenging Component

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孜然种子对奶牛养分摄入量和产奶量的影响

饲料博览 2016年第2期26卷 14-14页

作者： ghafari m Shahraki A D F Nasrollahi S m Amini H R Beauchemin K A

研究旨在确定奶牛日粮中添加孜然种子对奶牛营养摄入量、产奶量和血液代谢物的影响。试验选取平均产奶天数为35±5 d、平均体重660±15 kg的荷斯坦奶牛8头,采用4×4重复拉丁方设计,进行4个21 d的周期试验。试验中孜然的添加量分别为0(... 详细信息

研究旨在确定奶牛日粮中添加孜然种子对奶牛营养摄入量、产奶量和血液代谢物的影响。试验选取平均产奶天数为35±5 d、平均体重660±15 kg的荷斯坦奶牛8头,采用4×4重复拉丁方设计,进行4个21 d的周期试验。试验中孜然的添加量分别为0(对照组)、100、200和300 g·头·d-1,日粮为全混合日粮,饲喂4次·d-1。每个周期包括适应期14 d和采样期7 d,测定干物质采食量(DmI)、牛奶产量及组成和血液代谢物。试验表明,干物质采食量随着孜然添加量的增加而呈曲线增加(P≤0.05),孜然添加量为0、100、200、300 g·头·d-1时,干物质采食量分别为22.8、25.2、26.0和25.8 kg·d-1。同时,产奶量也随孜然添加量增加而显著增加(平均产奶量分别为47.9、52.5、55.1、53.6 kg·d-1,P≤0.05)。乳成分含量与产奶量增加趋势相似,但脂肪和4%脂肪校正乳产量无显著影响。随着日粮中孜然含量的增加,血液中葡萄糖、血尿素氮和β-羟丁酸的浓度无明显变化,但胆固醇浓度明显降低(P=0.08)。试验研究结果表明,泌乳奶牛日粮中补充孜然200 g·d-1可显著提高生产性能,而过量添加可能导致其效果降低。

关键词：孜然香精油生产性能血液代谢产物