A comparative study on the antioxidative and anti‐allergic activities of fresh and aged black garlic extracts

The antioxidative and anti‐allergic activities of fresh and aged black garlic extracts were investigated. The garlic samples were extracted with 70% ethanol (v/v) and the total phenolic content was measured. The antioxidant capacity of extracts was assessed by determining the scavenging activities on 1,1‐diphenyl‐2‐picrylhydrazyl and hydroxyl radicals, ferricyanide reducing power, ferrous ion‐chelating ability and inhibitory effect on linoleic acid peroxidation. The anti‐allergic activity of extracts was analysed by measuring their inhibitory effects against β‐hexosaminidase release. The aged black garlic exhibited significantly higher phenolic content and greater antioxidative activity than fresh garlic. Both garlic extracts showed strong antioxidant capacity in a dose‐dependent manner. On the other hand, a considerably higher suppression of β‐hexosaminidase release was found in fresh garlic extract at lower concentration compared with that of the black garlic. Results of this study illustrate that ageing of garlic could enhance its antioxidant capacity, but could decrease its anti‐allergic activity.     

Anti‐proliferative activity of bovine blood hydrolysates towards cancer cells in culture

Four proteins, α/β globulin, serum albumin, γ‐globulin and fibrinogen, were isolated from bovine blood and hydrolysed using papain. Hydrolysates were assessed for non‐cellular and cellular antioxidant activity. The anti‐proliferative activity of hydrolysed fractions was assessed in a number of cancer cell lines including U937 lymphoma cells, MCF‐7 breast cancer cells, HepG2 hepatocytes and Caco‐2 epithelial colorectal adenocarcinoma cells. Anti‐inflammatory activity of the hydrolysates was also assessed. Hydrolysates generated from γ‐globulin or fibrinogen had significant antioxidant activity in non‐cellular assays. Hydrolysates were also found to be highly toxic to different cancer cell lines, in particular U937 lymphoma cells when assessed using the MTT assay. The fibrinogen hydrolysate was the most toxic sample and toxicity appeared to correlate with its non‐cellular antioxidant activity. None of the hydrolysates had significant anti‐inflammatory activity. The high cytotoxicity of the γ‐globulin and the fibrinogen hydrolysates towards cancer cells may indicate a potential use as anti‐proliferative agents.     

Numerical simulation of rime ice accretion process on an airfoil

To simulate the ice accretion on an airfoil, a boundary moving technique is proposed to deal with the distortion of the airfoil surface due to ice accretion on the leading edge. Incorporating the two‐phase model of air‐supercooled droplets in the Eulerian coordinate system, this technique is applied to simulate the process of the rime ice accretion (the droplets freeze at the instant impinging on the airfoil) on the NACA 0012 airfoil, and the ice profile after ice accretion is achieved successfully. A brief comparison between the results of this paper and the experiment data indicates that the current method is applicable and effective. © 2005 Wiley Periodicals, Inc. Heat Trans Asian Res, 34(4): 226–234, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20064     

“黑灯库房”在山钢冷轧厂的实现与应用

针对当前轧钢企业智能工厂及智能物流的建设,介绍了“黑灯库房”在山钢日照公司冷轧厂轧后库和成品库的应用情况;主要对无人行车的硬件组成及关键技术,如防碰撞技术、智能扫描定位系统、吊具防摇摆技术、智能吊具系统等,进行了详细阐述,并对库管系统及其功能进行了介绍。实际应用表明,采用“黑灯库房”不仅能够带来良好的经济效益,而且库存周转更快、更高效,在安全上提供了更强有力的保障,使山钢日照公司智能制造水平有了较大提升,为下一步智能梦工厂的实现打下了良好的基础。     

重力坝抗滑稳定安全系数与安全度探讨

在进行深层抗滑稳定计算讨论时,涉及到的计算会变得相对复杂,会有更多的因素难以确定,并且由于在工程实践中的经验也累积较少,我们很难找到关于安全系数的一个统一标准取值。本文通过实际工程的计算给出抗滑稳定计算公式和安全系数的建议值,为以后的研究奠定基础。     

岩石锚杆在基坑抗浮中的应用

本文就岩石锚杆的设计与计算进行分析,结合某工程实例,就岩石锚杆在基坑抗浮中的应用进行详细的阐述。     

基于巴哈越野车的一种儿童赛车防倾装置

巴哈赛车是非常典型的高速越野型车辆,常在野外或沙地中行驶,大部分人尤其是青少年及儿童较难接触巴哈赛车并体验驾驶。若使儿童赛车能够实现安全、高速的巴哈赛车体验,有助于更早的让儿童接触中国的车辆知识,这对未来中国在汽车业的发展有所帮助。因此,采用对巴哈赛车的应力分析与物理计算方式,通过数据分析与控制系统改变车辆重心的方式,制造出有效防止儿童越野赛车倾倒的装置。使儿童越野车能够更安全的体验与发展。     

基于振动法的抗疲劳断裂水泥稳定碎石强度标准研究

强度是水泥稳定碎石材料设计与施工质量控制重要指标。当集料类型、矿料级配和成型方式一定情况下,水泥稳定碎石强度取决于水泥剂量。强度标准越高,则水泥剂量越大,水泥稳定碎石抗荷载破坏能力越强,但抗收缩开裂能力越差;反之亦然。为此,以水泥稳定碎石基层施工期和运营期在荷载作用下不发生疲劳破坏所需材料最小强度为准则,研究了水泥稳定碎石力学强度特性、疲劳特性及施工期与运营期水泥稳定碎石基层荷载响应,提出抗疲劳断裂的水泥稳定碎石强度标准。结果表明：为防止施工车辆荷载作用下基层发生极限断裂破坏,水泥稳定石灰岩碎石基层必须养护7d后,且其劈裂强度达到0.68MPa以上,方可进行下结构层施工;为防止设计年限内基层在施工车辆和运营车辆反复作用下产生疲劳断裂,水泥稳定石灰岩碎石7d劈裂强度不小于0.70MPa。为了便于应用,结合抗压强度和劈裂强度之间关系,提出水泥稳定石灰岩碎石7d抗压强度不小于7.0MPa。     

抗高过载微流体惯性开关

基于微连通器结构,提出了一种使用盐水(Na Cl溶液)作为工作流体且具有高的抗过载能力的微流体惯性开关。分析了液滴的分离机理,设计了开关的流道结构。然后,对开关进行了理论分析,建立了开关模型。最后,利用流体动力学仿真和样机实验相结合的方法,对开关结构和功能进行了验证。验证结果显示:在幅值为30 000 g阶跃型加速度作用下,开关的工作流体仍未发生分离,加速度的幅值与开关响应时间相关。另外,开关样机能够使盐水液面形成高度差,样机的静态加速度阈值为134.6 g~152.3 g,非常接近其理论计算的加速度阈值142.7 g。得到的结果表明,采用的微连通器结构能够极大地增强微流体惯性开关的抗液体分离能力,能够对加速度幅值进行区分,并实现闭锁功能,同时显示了高的抗过载能力。