Current and potential uses of bioactive molecules from marine processing waste

Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti‐oxidant, anti‐coagulant, anti‐thrombotic, anti‐cancer and immune‐stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry     

Dynamical Study of Pulsed Impinging Jet with Time Varying Heat Flux Boundary Condition

Pulsed jets in different configuration are potentially considered for enhancing transport phenomenon generally. Flow and temperature field in a pulsed impinging jet are simulated numerically by solving the governing equations using the control volume method. Ensemble Averaging Method as well as Phase Averaging has been employed for reporting the results in this study. In order to simulate a pulsating jet, inlet velocity profile was exerted as a time dependent sinusoidal and step signals. The results of this simulation showed an oscillatory jet could lead to an increase in jet development and its cross section with the wall and also a more uniform Nusselt profile would be obtained compared to the steady jet. For parametric investigations and extracting flow and thermal characteristics of a pulsed impinging jet, the effects of various parameters including flow frequency and amplitude and heat flux frequency were considered. It has been seen that Nusselt number varies by the changes in frequency, amplitude and the type of the excitation. It has been shown that the oscillating impinging jet has a better performance rather than the steady case when the excitation amplitude and frequency increase. Finally, it is also observed how a thermal field is going to respond with two pulsating inputs.     

基于空间信息技术的六股河流域河网水系提取

快速有效地获取河网水系特征信息对于流域水文分析具有重要的意义。为此,选取辽宁省六股河流域作为研究对象,以30 m空间分辨率的数字高程模型(DEM)作为基础数据,采用美国ESRI公司开发的地理信息系统软件ArcGIS,对该流域的水流方向、累积汇流栅格、河网水系等基础信息进行了提取研究。将河网提取结果与国家基础信息中心提供的1∶4 000 000河流水系基础资料进行对比,提取结果的干流河网段与实际水系形态特征较为吻合,提取的流域面积与实际流域面积相差1.99%,表明空间信息技术应用于六股河流域水文基础信息提取是可行的,可为流域水文模拟、数字流域建设等研究提供基础数据支持。     

APPROPRIATE SIZES OF POROUS AND SOLID BLOCKS FOR HEAT TRANSFER UNDER AN IMPINGING JET

ABSTRACT

A study of appropriate sizes of both porous and solid blocks mounted on a heated region impinged by a laminar slot jet was investigated numerically. A numerical method of SIMPLEC is adopted to solve governing equations, and a one-equation thermal model with Van Driest's wall function is considered for solving the energy equation of the porous block. The results indicated that enhancement of heat transfer is obtained for both shorter porous and solid block cases and decreasement of heat transfer occurs for longer block cases. Compared with the without block case, there exists an appropriate length of the porous block to gain the maximum thermal enhancement efficiency. As for the solid block case, as the length becomes shorter, the thermal enhancement efficiency becomes better.     

两喷嘴对置撞击流驻点偏移规律

运用烟线法和热线风速仪对两喷嘴撞击流流场进行了实验研究,考察了不同喷嘴间距、不同气速比下撞击面的稳定性和撞击面驻点的偏移规律。结果发现,当2D≤L≤4D（L为喷嘴间距,D为喷嘴直径）时,若两喷嘴气速相等,撞击面不稳定,在轴线上发生振荡;当两喷嘴气速有小的差异时,撞击面驻点将发生大幅度的偏移,此时流场变得相对比较稳定。当2D≤L≤8D时,撞击面驻点位置对气速比变化很敏感;当L<2D和L>8D时,撞击面驻点位置对两喷嘴气速比的变化逐渐变得不敏感。     

撞击流对火焰稳定性影响的试验研究

研究了射流火焰噪声和撞击式火焰噪声,对比两者以探求撞击流对火焰稳定性的影响。对火焰噪声信号进行频谱分析（FFT）,结果表明,射流火焰噪声包含燃烧噪声和喷流噪声,火焰噪声以燃烧噪声为主,撞击式火焰噪声是主频约420Hz的高频噪声,由燃烧噪声、喷流噪声和撞击区燃烧噪声组成。撞击式火焰噪声频谱图表明,撞击流强化了气化燃烧,有利于火焰的稳定,对气化炉的稳定运行有重大意义。     

撞击流反应器撞击区流动特性研究

为研究撞击区的流动特性,在有效容积为160 L的撞击流反应器内,以水为介质,饱和KCl溶液为示踪剂,用电导法测定了不同导流筒出口间距和撞击流速下的示踪剂浓度曲线,并通过多釜串联模型拟合得到了撞击区的平均停留时间及模拟釜数。结果表明:导流筒出口间距减小,撞击流速增大,撞击区平均停留时间减小,釜数减小;撞击流速为2.0 m/s时,撞击区内流型接近于全混流。停留时间分布主要受撞击流速的影响,增大流速有利于促进撞击区中的宏观混合。     

孔排射流冲击换热过程数值模拟研究及结构优化

运用数值仿真技术对带钢连续热处理快速冷却过程中的孔排射流冲击换热进行了三维数值模拟,主要研究了几何参数对射流冲击传热特性的影响规律。在研究的参数范围内,获得了孔排射流冲击换热装置的最优结构。分析表明:展向孔间距S2的影响最为显著,其次是流向孔间距S1,板间距H的影响作用最小。     

单孔射流冲击流动与换热过程的数值模拟

应用三种RNG k-ε湍流模型对单孔气体射流冲击流动与换热过程进行了数值仿真计算,与实验结果的比较分析表明;RNG k-e系列模型能够对射流冲击流动和换热过程进行较为准确的预测.在此基础上,进一步对局部Nu数、平均Nu数分布的分析表明:喷孔直径D对冲击点处Nu的数值大小无明显影响;射流冲击高度HI/D对Nu数的分布规律...     

新型多参数水质分析仪流路控制系统的设计

以单片机为核心,运用十联体电磁阀、三通阀和微型步进蠕动泵等流控器件设计新型多流路控制系统.对比测试结果表明,该系统能完成20多种流路切换,进样速度快,加样误差小于1%,能快速、高效地清洗进样通道,并避免交叉污染,而且成本低、不易堵塞、稳定性良好.