mechanical energy
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2022 ◽  
Vol 607 ◽  
pp. 412-422 ◽  
Author(s):  
Xiaojing Li ◽  
Junfeng Wang ◽  
Jiayu Zhang ◽  
Chunran Zhao ◽  
Ying Wu ◽  
...  

2022 ◽  
Author(s):  
Huifang Xu ◽  
Kuang-Sheng Hong ◽  
Meiye Wu ◽  
Seungyeol Lee

ABSTRACT A high concentration of hydrogen gas occurs in fracture zones of active faults that are associated with historical earthquakes. To explain the described phenomenon, we propose the piezoelectrochemical (PZEC) effect as a mechanism for the direct conversion of mechanical energy to chemical energy. When applied to natural piezoelectric crystals including quartz and serpentine, hydrogen and oxygen are generated via direct water decomposition. Laboratory experiments show H2 gas is generated from strained piezoelectric material due to the extremely low solubility of H2, suggesting that the deformed or strained mineral surfaces can catalyze water decomposition. If the strain-induced H2 production is significant, hydrogen measurements at monitoring sites can offer information on deformation of rocks operating at depth prior to earthquakes. Oxygen can be measured in water due to its high solubility compared to hydrogen. Our experimental results demonstrate that dissolved oxygen generated from the PZEC effect can oxidize dissolved organic dye and ferrous iron in an aqueous Fe(II)–silicate metal complex. The hydrogen and oxygen formed through stoichiometric decomposition of water in the presence of strained or deformed minerals in fault zones (including subduction zones and transform faults) may be referred to as tectonic hydrogen and tectonic oxygen. Tectonic hydrogen could be a potential energy source for deep subsurface and glacier-bedrock interface microbial communities that rely on molecular hydrogen for metabolism. Tectonic oxygen may have been an important oxidizing agent when dissolved in water during times in early Earth history when atmospheric oxygen levels were extremely low. Reported “whiffs” of dissolved oxygen before the Great Oxidation Event might have been related to tectonic activity.


Author(s):  
Asif Abdullah Khan ◽  
Resul Saritas ◽  
Md Masud Rana ◽  
Nicolas Tanguy ◽  
Weiguang Zhu ◽  
...  

Author(s):  
Aditya Singh ◽  
Manish Thakur ◽  
Akshat shah ◽  
Neerake Bajaj ◽  
Hardik Taneja ◽  
...  

Each and every automobile in service or being developed in the industry is benchmarked on the basis of its efficiency in running real conditions. So in our project here we have tried to develop a complete new damper and spring setup which can be used in all sorts of suspension systems and in turn provides a feedback loop of voltage which can then be used charge the batteries and upscale the efficiency of bikes by (5-6)% & and for HUV or Sedans by (2-4)% (can even go higher) depending on the terrain. In this setup we harness the mechanical energy into electrical where earlier it was left as heat and vibrational losses. This setup is as cost effective as the earlier dampers where as providing an efficient output in minimal cost increase due to its novelty. The other Features include Electronic height adjustment & on demand suspension softness or stiffness. Keywords: Dampers, Automobile, Electromagnet, EV (Electric vehicle), Voltage, Magnetic flux, Suspension


2022 ◽  
Vol 51 (4) ◽  
pp. 768-778
Author(s):  
Sergey Rudnev ◽  
Tatyana Shevchenko ◽  
Yulia Ustinova ◽  
Roman Kryuk ◽  
Viktor Ivanov ◽  
...  

Introduction. Bakery products are an important part of traditional Russian menu. Activated water helps to improve the quality of flour products. The present research objective was (1) to activate water with mechanical energy to change the physicochemical properties of the dough; (2) to evaluate the energy efficiency of the new technological process, and (3) to determine the quality indicators of bread. Study objects and methods. The research featured high quality wheat flour, drinking water, and pressed baking yeast (Saccharomyces cerevisiae). Standard research methods were used to assess the physical and chemical properties of water, namely acidity index (pH), surface tension coefficient, and biological activity. The physico-chemical properties of the dough were studied by maximum shear stress and adhesion. Results and discussion. The samples of activated water demonstrated the following technological properties. Its acidity due decreased as pH fell down to 6.05. With a total mixing time of 10 min, the surface tension decreased by about 10%; after 5 min, it decreased by 4%, while the biological activity of activated water increased by 1.5 times. Mechanically treated water used for bread production contributed to the overall energy saving during kneading and increased its water-binding ability. Moisture removal was by 30–40% more intensive than in the control dough sample. Also, the quality of gluten changed as a result of higher shear stress, which gave the experimental dough better forming properties necessary for the production of high-quality bread. The mechanically activated water increased the specific volume of bread from 2.05 to 2.38 cm3/g. Conclusion. The activated water improved the physico-chemical and rheological properties of dough, as well as the main sensory indicators of bread, e.g. porosity and bread crumb elasticity.


2022 ◽  
pp. 2109492
Author(s):  
Thangavel Vijayakanth ◽  
David J. Liptrot ◽  
Ehud Gazit ◽  
Ramamoorthy Boomishankar ◽  
Chris R. Bowen

2022 ◽  
Vol 11 (2) ◽  
pp. 331-344
Author(s):  
Xiangxin Du ◽  
Zheng Zhou ◽  
Zhao Zhang ◽  
Liqin Yao ◽  
Qilong Zhang ◽  
...  

AbstractPiezoelectric nanogenerators (PENGs) that can harvest mechanical energy from ambient environment have broad prospects for multi-functional applications. Here, multi-layered piezoelectric composites with a porous structure based on highly oriented Pb(Zr0.52Ti0.48)O3/PVDF (PZT/PVDF) electrospinning fibers are prepared via a laminating method to construct high-performance PENGs. PZT particles as piezoelectric reinforcing phases are embedded in PVDF fibers and facilitate the formation of polar β phase in PVDF. The multi-layered, porous structure effectively promotes the overall polarization and surface bound charge density, resulting in a highly efficient electromechanical conversion. The PENG based on 10 wt% PZT/PVDF composite fibers with a 220 µm film thickness outputs an optimal voltage of 62.0 V and a power of 136.9 µW, which are 3.4 and 6.5 times those of 10 wt% PZT/PVDF casting film-based PENG, respectively. Importantly, the PENG shows a high sensitivity of 12.4 V·N−1, presenting a significant advantage in comparison to PENGs with other porous structures. In addition, the composites show excellent flexibility with a Young’s modulus of 227.2 MPa and an elongation of 262.3%. This study shows a great potential application of piezoelectric fiber composites in flexible energy harvesting devices.


eLife ◽  
2022 ◽  
Vol 11 ◽  
Author(s):  
Osman Darici ◽  
Arthur D Kuo

The simple task of walking up a sidewalk curb is actually a dynamic prediction task. The curb is a disturbance that could cause a loss of momentum if not anticipated and compensated for. It might be possible to adjust momentum sufficiently to ensure undisturbed time of arrival, but there are infinite possible ways to do so. Much of steady, level gait is determined by energy economy, which should be at least as important with terrain disturbances. It is, however, unknown whether economy also governs walking up a curb, and whether anticipation helps. Here we show that humans compensate with an anticipatory pattern of forward speed adjustments, predicted by a criterion of minimizing mechanical energy input. The strategy is mechanistically predicted by optimal control for a simple model of bipedal walking dynamics, with each leg's push-off work as input. Optimization predicts a tri-phasic trajectory of speed (and thus momentum) adjustments, including an anticipatory phase. In experiment, human subjects ascend an artificial curb with the predicted tri-phasic trajectory, which approximately conserves overall walking speed relative to undisturbed flat ground. The trajectory involves speeding up in a few steps before the curb, losing considerable momentum from ascending it, and then regaining speed in a few steps thereafter. Descending the curb entails a nearly opposite, but still anticipatory, speed fluctuation trajectory, in agreement with model predictions that speed fluctuation amplitudes should scale linearly with curb height. The fluctuation amplitudes also decrease slightly with faster average speeds, also as predicted by model. Humans can reason about the dynamics of walking to plan anticipatory and economical control, even with a sidewalk curb in the way.


Athenea ◽  
2022 ◽  
Vol 2 (6) ◽  
pp. 28-42
Author(s):  
Alberto Echegaray

This article presents an approach to the problem of ceramic types adhesion, applying energy and matter balance to the established control volume (cyclone) with the use of mathematical formulas that are interrelated to develop mathematical calculations and establish a new mathematical model The first results are obtained by operating the energy balance considering the collision of particles, using the principle of conservation of energy, the first law of thermodynamics, in order to obtain information that allows describing the phenomena of thermoplasticity and creep, in the formation of adhesions, from a physicochemical and kinetic point of view, which will serve as the basis for understanding their effect. As a result, an energy value of 660 kJ / mol was obtained, sufficient energy to start the transformation of the solid particles to a state of thermo-flow that allows the adhesion phenomenon to be started. Keywords: Adhesion, energy balance, cyclones, elutriation, eutectoid, fayalite, thermoplasticity. References [1]O. Bustamante. “Dissipation of mechanical energy in the discharge of a hydrocyclone”. (Dyna, Ed.) The network of Scientific Journals of Latin America, the Caribbean, Spain, and Portugal, vol. 80 (181), Pages 136-143, 2013. [2]K.Petersen, P.Aldrich, and D.Van.,”Hydrocyclone underflow monitoring using image processing methods. Minerals Engineering”, pp. 301-315,1996. [3]M. Farghaly,” Controlled Wash Water Injection to the hydrocyclone underflow” [Ph.D. Thesis]. Erlangen, FAU, 2009. [4]M, Schneider, and T. Neesse. “Overflow-control system for a hydrocyclone battery. Int. J. Miner. Process". 74, pp. 339 – 343, 2004. [5]J.Bergström., “Flow field and fiber fractionation studies in hydro cyclones” [Ph.D. Thesis] Stockholm, Sweden, Royal Institute of Technology, 2006. [6]C, Liu, L. Wang, and Q. Lui., “Investigation of energy loss mechanisms in cyclone separators”. Chemical Engineering Technology 28, pp. 1182-1190, 2005. [7]O.Dam. & E.Jeffes.,.”Model for detailed assessment of chemical composition of reduced iron ores from single measurement”. Ironmaking and Steelmaking, 1987. [8]E. Ringdalen., “Softening and melting of SiO2 an important parameter for reactions with quartz in Si production” pp 43-44, 2016.


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