Management of stream compensation for a large conjunctive use scheme,Shropshire, UK

The Shropshire Groundwater Scheme (SGS) is the largest conjunctive use scheme in the United Kingdom. The SGS operates in drought periods, pumping water from the Permo‐Triassic Sandstone aquifer in Shropshire, England to regulate flows in the River Severn, alongside releases from conventional surface water reservoirs. This regulation protects the environment and increases the security of supply of major public water supply abstractions downstream. An important operational consideration is the impact SGS groundwater abstraction has on small streams that rise on the Shropshire Permo‐Triassic Sandstone. Compensation boreholes have been installed to maintain flows during and after the operation of the SGS. This paper shows how a groundwater model of the East Shropshire Permo‐Triassic Sandstone has been used to estimate the required level of compensation flows for recent climatic conditions to optimise the use of the SGS. The catchment wide conditions are included in this analysis by using the results of a large‐scale surface water model of the River Severn.     

Algal capture of carbon dioxide; biomass generation as a tool for greenhouse gas mitigation with reference to New Zealand energy strategy and policy

The use of algae to capture carbon dioxide as a method for greenhouse gas mitigation is discussed. A small fraction of the sunlight energy that bathes Earth is captured by photosynthesis and drives most living systems. Life on Earth is carbon-based and the energy is used to fix atmospheric carbon dioxide into biological material (biomass), indeed fossil fuels that we consume today are a legacy of mostly algal photosynthesis. Algae can be thought of as marine and freshwater plants that have higher photosynthetic efficiencies than terrestrial plants and are more efficient capturing carbon (Box 1). They have other favourable characteristics for this purpose. In the context of New Zealand energy strategy and policy I discuss progress in growing algae and seaweeds with emphasis on their application for exhaust flue carbon recycling for possible generation of useful biomass. I also introduce schemes utilising wild oceanic algae for carbon dioxide sequestration and the merits and possible adverse effects of using this approach. This paper is designed as an approachable review of the science and technology for policy makers and a summary of the New Zealand policy environment for those wishing to deploy biological carbon sequestration.     

用FPGA设计引擎安全监测仪实现创业

并非只有宇宙才诞生于大爆炸。目前硅谷最火的汽车电子新创企业PLX Devices也诞生于创始人的引擎爆炸。PLX最新的产品是一款能够监测汽油使用状况,鼓励节油驾驶的插入式器件。它源自公司28岁的首席执行官Paul Lowchareonkul在驾车与奔驰赛车跑坏了引擎后发明的一个空气燃油比测量仪。这两款器件均采用了赛灵思FPGA平台。     

军用无源器件的发展趋势

军工/航天和商用电子元器件市场常常被认为是两个不同的市场,但实际上,二者之间的共同之处正在不断增加。由于高可靠性业务的数量显著较少,该领域的采购商似乎把目光放在商业客户的对应型号上,当然前提是满足起码的性能要求。这些采购商开始仿照商用标准产品的客户,越来越多地通过分销商来采购所需的元器件。那些军工和航天领域的巨头不再局限于原有的垂直集成业务模式,开始象那些商业OEM厂商一样,考虑将电路板组装业务通过离岸合同制造的方式外包出去,以降低他们的成本。     

Correlation of omega-3 levels in serum phospholipid from 2053 human blood samples with key fatty acid ratios

Background  

This research was conducted to explore the relationships between the levels of omega-3 fatty acids in serum phospholipid and key fatty acid ratios including potential cut-offs for risk factor assessment with respect to coronary heart disease and fatal ischemic heart disease.     

The effects of creatine ethyl ester supplementation combined with heavy resistance training on body composition, muscle performance, and serum and muscle creatine levels

Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester is alleged to increase creatine bio-availability. This study examined how a seven-week supplementation regimen combined with resistance training affected body composition, muscle mass, muscle strength and power, serum and muscle creatine levels, and serum creatinine levels in 30 non-resistance-trained males. In a double-blind manner, participants were randomly assigned to a maltodextrose placebo (PLA), creatine monohydrate (CRT), or creatine ethyl ester (CEE) group. The supplements were orally ingested at a dose of 0.30 g/kg fat-free body mass (approximately 20 g/day) for five days followed by ingestion at 0.075 g/kg fat free mass (approximately 5 g/day) for 42 days. Results showed significantly higher serum creatine concentrations in PLA (p = 0.007) and CRT (p = 0.005) compared to CEE. Serum creatinine was greater in CEE compared to the PLA (p = 0.001) and CRT (p = 0.001) and increased at days 6, 27, and 48. Total muscle creatine content was significantly higher in CRT (p = 0.026) and CEE (p = 0.041) compared to PLA, with no differences between CRT and CEE. Significant changes over time were observed for body composition, body water, muscle strength and power variables, but no significant differences were observed between groups. In conclusion, when compared to creatine monohydrate, creatine ethyl ester was not as effective at increasing serum and muscle creatine levels or in improving body composition, muscle mass, strength, and power. Therefore, the improvements in these variables can most likely be attributed to the training protocol itself, rather than the supplementation regimen.     

Understanding particle dynamics in erosion testers—A review of influences of particle movement on erosion test conditions

An understanding of particle dynamics is important when determining material erosive wear in any erosion tester, because particle impact conditions are primarily influenced by particle acceleration. A better understanding of particle dynamics in the testers will aid the control of erosion test conditions and therefore improve the accuracy of measurement. In this paper, particle dynamics in the two most popular erosion testers, the centrifugal erosion tester and the gas-blast erosion tester, has been discussed in detail. Mechanisms of particle acceleration in the two types of testers were explored and computational models of particle dynamics were described briefly. A review of the experimental determination of important characteristics of particle dynamics (such as particle velocity, particle trajectory, particle dispersion and particle rotation) showed how they influenced particle movement and therefore the particle impact conditions. In addition, comparison of the particle dynamics in the two types of erosion testers showed that differences of particle acceleration may lead to significantly different results at identical pre-set test conditions. It may be concluded that it is not possible to directly compare the results obtained in different types of erosion testers even under notionally identical test conditions.     

Drought Severity Assessment Based on Bivariate Probability Analysis

Conventionally drought severity is assessed based on drought indices. Recently the Reconnaissance Drought Index (RDI) was proposed to assess drought severity based on the precipitation to potential evapotranspiration ratio (P/PET). In this paper RDI is studied as a bivariate index under a set of assumptions and simplifications. The paper presents a simple computational procedure for estimating the P/PET ratio for selected reference periods varying from 3 to 12 months, for any return period of drought. Alternatively, based on this procedure, the severity of any drought episode is rationally assessed. A bivariate probability analysis is employed based on the assumption that P and PET values are normally distributed and often negatively correlated. Examples for the application of the proposed procedure are presented using data from several meteorological stations in Greece. It is shown that the assumption of normality of both P and PET holds for long periods at all examined stations.     

Activation of microcomponents with light for micro-electro-mechanical systems and micro-optical-electro-mechanical systems applications

We examine the light-activation properties of micrometer-sized gear structures fabricated with polysilicon surface micromachining techniques. The gears are held in place on a substrate through a capped anchor post and are free to rotate about the post. The light-activation technique is modeled on photon radiation pressure, and the equation of motion of the gear is solved for this activation technique. Experimental measurements of torque and damping are found to be consistent with expected results for micrometer-scale devices. Design optimization for optically actuated microstructures is discussed.