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991.
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Nirmal J. Nair Maciej Balajewicz 《International journal for numerical methods in engineering》2019,117(12):1234-1262
A new model order reduction approach is proposed for parametric steady-state nonlinear fluid flows characterized by shocks and discontinuities whose spatial locations and orientations are strongly parameter dependent. In this method, solutions in the predictive regime are approximated using a linear superposition of parameter-dependent basis. The sought-after parametric reduced bases are obtained by transporting the snapshots in a spatially and parametrically dependent transport field. Key to the proposed approach is the observation that the transport fields are typically smooth and continuous, despite the solution themselves not being so. As a result, the transport fields can be accurately expressed using a low-order polynomial expansion. Similar to traditional projection-based model order reduction approaches, the proposed method is formulated mathematically as a residual minimization problem for the generalized coordinates. The proposed approach is also integrated with well-known hyper-reduction strategies to obtain significant computational speedups. The method is successfully applied to the reduction of a parametric one-dimensional flow in a converging-diverging nozzle, a parametric two-dimensional supersonic flow over a forward-facing step, and a parametric two-dimensional jet diffusion flame in a combustor. 相似文献
993.
Eco-driving has been proposed as an approach to significantly reduce greenhouse gas emissions arising from personal automobile use. Eco-driving is the adoption of a measured driving style, minimising unnecessary breaking and aggressive acceleration. Eco-driving can be seen as a low cost and immediate approach to emission reduction as it involves the modification of drivers’ behaviours as opposed to the development and implementation of newer, more efficient technology. Despite the proposed benefits of eco-driving, numerous challenges are faced in order to encourage the adoption of these behaviours and maintain them long term. This narrative review presents the concept of eco-driving, with a focus on the long-term maintenance of these behaviours, including training programmes and feedback devices. It is clear within current literature that, despite the economic and environmental benefits of adopting eco-driving, drivers require feedback on their actions in order to promote long-term, behavioural, change. 相似文献
994.
Chia‐Che Chang Sin‐Ren Li Hung‐Lung Chou Yi‐Cheng Lee Shivaraj Patil Ying‐Sheng Lin Chun‐Chih Chang Yuan Jay Chang Di‐Yan Wang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(49)
The generation of ammonia, hydrogen production, and nitrogen purification are considered as energy intensive processes accompanied with large amounts of CO2 emission. An electrochemical method assisted by photoenergy is widely utilized for the chemical energy conversion. In this work, earth‐abundant iron pyrite (FeS2) nanocrystals grown on carbon fiber paper (FeS2/CFP) are found to be an electrochemical and photoactive catalyst for nitrogen reduction reaction under ambient temperature and pressure. The electrochemical results reveal that FeS2/CFP achieves a high Faradaic efficiency (FE) of ≈14.14% and NH3 yield rate of ≈0.096 µg min?1 at ?0.6 V versus RHE electrode in 0.25 m LiClO4. During the electrochemical catalytic reaction, the crystal structure of FeS2/CFP remains in the cubic pyrite phase, as analyzed by in situ X‐ray diffraction measurements. With near‐infrared laser irradiation (808 nm), the NH3 yield rate of the FeS2/CFP catalyst can be slightly improved to 0.1 µg min?1 with high FE of 14.57%. Furthermore, density functional theory calculations demonstrate that the N2 molecule has strong chemical adsorption energy on the iron atom of FeS2. Overall, iron pyrite‐based materials have proven to be a potential electrocatalyst with photoactive behavior for ammonia production in practical applications. 相似文献
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Investigation of technological approaches for reduction of methanol formation in plum wines 下载免费PDF全文
Uroš Miljić Vladimir Puškaš Vesna Vučurović 《Journal of the Institute of Brewing》2016,122(4):635-643
Methanol is natural ingredient of alcoholic beverages and soft drinks; however, the products of its metabolic transformations (formaldehyde and formic acid) are toxic to humans. The aim of this research was to assess the application of different physico‐chemical treatments of pomace in order to find the most efficient method for reducing the methanol during fermentation with the least effect on the sensory properties of the wine. The following procedures were studied: addition of tannins in pomace, addition of phenolic acids, addition of d ‐galacturonic and pectic acid, use of bentonite and zeolite, heat treatment of pomace, thermosonication and treatment of pomace with microwaves. Fruit wine used in this study was produced from plums (Prunus domestica L.). Applied treatments showed variable efficiency in reduction of methanol formation in plum wine. It may be noted that the procedures that involved some form of thermal treatment were characterized by a significant decrease in the production of methanol (up to 60–70%) but mostly tended to have a negative impact on the sensory properties of the produced wines. However, exposure of pomace to microwaves for a short time, owing to the contribution of mechanisms of non‐thermal nature (kinetic and chemical), allowed for a significant reduction in methanol formation with a negligible impact on the sensory properties. The decrease in methanol formation during fermentation using tannins, pectic acid, bentonite and zeolite was poor, with only a reduction of up to 15%. Obtained results are significant to the fruit wine and spirit industry, considering the common problem related to an increased content of methanol in these beverages. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
998.
食品机械的设计方法将直接影响其制造加工方式、制造加工周期、使用过程和废弃后处置等环节.通过分析传统的串行式的设计模式所存在的问题,从食品机械的全生命周期中对环境的影响角度,提出了应用并行式绿色设计方法,以提高食品机械的质量和绿色度、缩短开发周期,降低食品机械生命周期内成本.指出并行式绿色设计是食品机械制造业实施可持续发展战略、解决环境污染问题、实现新的经济增长的必由之路. 相似文献
999.
As a result of their use in detergents and personal products and their subsequent disposal, anionic surfactants may achieve a wide distribution in the environment. It is therefore important to assess the hazard that this use might present to the environment.
In order to do this it is necessary to estimate the highest concentrations which are likely to occur at key points in the environment. These estimates may be based on a knowledge of the quantities used and the per capita consumption of water, and take account of the physico-chemical properties, biodegradation and treatability of the surfactant. The margin of safety between these estimates and the lowest concentrations causing adverse effects on sewage treatment operations, aquatic organisms and crops may then be determined.
Laboratory studies on linear alkyl benzene sulphonates, primary alkyl sulphates, linear alkyl ether sulphates and secondary alkane sulphonates suggest that their current levels in detergents and personal products present no hazard to the environment. This conclusion is confirmed by the results of environmental monitoring.
Les agents de surface et l'environment 相似文献
In order to do this it is necessary to estimate the highest concentrations which are likely to occur at key points in the environment. These estimates may be based on a knowledge of the quantities used and the per capita consumption of water, and take account of the physico-chemical properties, biodegradation and treatability of the surfactant. The margin of safety between these estimates and the lowest concentrations causing adverse effects on sewage treatment operations, aquatic organisms and crops may then be determined.
Laboratory studies on linear alkyl benzene sulphonates, primary alkyl sulphates, linear alkyl ether sulphates and secondary alkane sulphonates suggest that their current levels in detergents and personal products present no hazard to the environment. This conclusion is confirmed by the results of environmental monitoring.
Les agents de surface et l'environment 相似文献
1000.