pinecone/core-2020-05-10-deduplication huggingface dataset:
On the ocean heat budget and ocean thermal energy conversion

Ocean water covers a vast portion of the Earth's surface and is also the world's largest solar energy collector. It plays an important role in maintaining the global energy balance as well as in preventing the Earth's surface from continually heating up because of solar radiation. The ocean also plays an important role in driving the atmospheric processes. The heat exchange processes across the ocean surface are represented in an ocean thermal energy budget, which is important because the ocean stores and releases thermal energy. The solar energy absorbed by the ocean heats up the surface water, despite the loss of heat energy from the surface due to back-radiation, evaporation, conduction, and convection, and the seasonal change in the surface water temperature is less in the tropics. The cold water from the higher latitudes is carried by ocean currents along the ocean bottom from the poles towards the equator, displacing the lower-density water above and creating a thermal structure with a large reservoir of warm water at the ocean surface and a large reservoir of cold water at the bottom, with a temperature difference of 22°C to 25°C between them. The available thermal energy, which is the almost constant temperature water at the beginning and end of the thermocline, in some areas of the oceans, is suitable to drive ocean thermal energy conversion (OTEC) plants. These plants are basically heat engines that use the temperature difference between the surface and deep ocean water to drive turbines to generate electricity. A detailed heat energy budget of the ocean is presented in the paper taking into consideration all the major heat inputs and outputs. The basic OTEC systems are also presented and analyzed in this paper
Melting of PCM in a thermal energy storage unit: Numerical investigation and effect of nanoparticle enhancement

The present paper describes the analysis of the melting process in a single vertical shell-and-tube latent heat thermal energy storage (LHTES), unit and it is directed at understanding the thermal performance of the system. The study is realized using a computational fluid-dynamic (CFD) model that takes into account of the phase-change phenomenon by means of the enthalpy method. Fluid flow is fully resolved in the liquid phase-change material (PCM) in order to elucidate the role of natural convection. The unsteady evolution of the melting front and the velocity and temperature fields is detailed. Temperature profiles are analyzed and compared with experimental data available in the literature. Other relevant quantities are also monitored, including energy stored and heat flux exchanged between PCM and HTF. The results demonstrate that natural convection within PCM and inlet HTF temperature significantly affects the phase-change process. Thermal enhancement through the dispersion of highly conductive nanoparticles in the base PCM is considered in the second part of the paper. Thermal behavior of the LHTES unit charged with nano-enhanced PCM is numerically analyzed and compared with the original system configuration. Due to increase of thermal conductivity, augmented thermal performance is observed: melting time is reduced of 15% when nano-enhanced PCM with particle volume fraction of 4% is adopted. Similar improvements of the heat transfer rate are also detecte
Effectiveness of smart charging of electric vehicles under power limitations

This article investigates charging strategies for plug-in hybrid electric vehicles (PHEV) as part of the energy system. The objective was to increase the combined all-electric mileage (total distance driven using only the traction batteries in each PHEV) when the total charging power at each workplace is subject to severe limitations imposed by the energy system. In order to allocate this power optimally, different input variables, such as state-of-charge, battery size, travel distance, and parking time, were considered. The required vehicle mobility was generated using a novel agent-based model that describes the spatiotemporal movement of individual PHEVs. The results show that, in the case of Helsinki (Finland), smart control strategies could lead to an increase of over 5% in the all-electric mileage compared to a no-control strategy. With a high prediction error, or with a particularly small or large battery, the benefits of smart charging fade off. Smart PHEV charging strategies, when applied to the optimal allocation of limited charging power between the cars of a vehicle fleet, seem counterintuitively to provide only a modest increase in the all-electric mileage. A simple charging strategy based on allocating power to PHEVs equally could thus perform sufficiently well. This finding may be important for the future planning of smart grids as limiting the charging power of larger PHEV fleets will sometimes be necessary as a result of grid restrictions.Peer reviewe
Thermodynamic analysis and performance optimization of organic rankine cycles for the conversion of low-to-moderate grade geothermal heat

The present study considers a thermodynamic analysis and performance optimization of
geothermal power cycles. The proposed binary-cycles operate with moderately low
temperature and liquid-dominated geothermal resources in the range of 110oC to 160oC, and
cooling air at ambient conditions of 25oC and 101.3 kPa reference temperature and
atmospheric pressure, respectively. A thermodynamic optimization process and irreversibility
analysis were performed to maximize the power output while minimizing the overall exergy
destruction and improving the First- and Second-law efficiencies of the cycle. Maximum net
power output was observed to increase exponentially with the geothermal resource
temperature to yield 16-49 kW per unit mass flow rate of the geothermal fluid for the nonregenerative
ORCs, as compared to 8-34 kW for the regenerative cycles. The cycle First-law
efficiency was determined in the range of 8-15% for the investigated geothermal binary
power cycles. Maximum Second-law efficiency of approximately 56% was achieved by the
ORC with an IHE. In addition, a performance analysis of selected pure organic fluids such as
R123, R152a, isobutane and n-pentane, with boiling points in the range of -24oC to 36oC, was
conducted under saturation temperature and subcritical pressure operating conditions of the
turbine. Organic fluids with higher boiling point temperature, such as n-pentane, were
recommended for non-regenerative cycles. The regenerative ORCs, however, require organic
fluids with lower vapour specific heat capacity (i.e. isobutane) for an optimal operation of the
binary-cycle.Hitachi Power Africa and the National Research Foundation (NRFDST).http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-114X2016-07-31hb201
Wells turbine for wave energy conversion : a review

In the past twenty years, the use of wave energy systems has significantly increased, generally depending on the oscillating water column (OWC) concept. Wells turbine is one of the most efficient OWC technologies. This article provides an updated and a comprehensive account of the state of the art research on Wells turbine. Hence, it draws a roadmap for the contemporary challenges which may hinder future reliance on such systems in the renewable energy sector. In particular, the article is concerned with the research directions and methodologies which aim at enhancing the performance and efficiency of Wells turbine. The article also provides a thorough discussion of the use of computational fluid dynamics (CFD) for performance modeling and design optimization of Wells turbine. It is found that a numerical model using the CFD code can be employed successfully to calculate the performance characteristics of W-T as well as other experimental and analytical methods. The increase of research papers about CFD, especially in the last five years, indicates that there is a trend that considerably depends on the CFD method
An assessment of the viability of hydrogen generation from the reaction of silicon powder and sodium hydroxide solution for portable applications

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution andreproduction in any medium, provided the original work is properly cited.The gravimetric hydrogen storage efficiency of silicon has been widely reported as 14wt.%, suggesting that this material should be an excellent hydrogen generation source for portable applications. However, in the case of the reaction of silicon powder with 20wt.% sodium hydroxide solution at 50°C, the observed production of hydrogen fails to realize these high expectations unless a large excess of basic solution is used during the reaction, rendering the use of silicon in such systems uncompetitive compared with chemical hydride based technologies. By investigating the molar ratio of water:silicon from a large excess of water towards the stoichiometric 2:1 ratio dictated by the reaction equation, this study shows that for the reaction of silicon in 20wt.% sodium hydroxide solution, the quantity of hydrogen produced decreases as the 2:1 ratio expected from the equation for the reaction is approached. Furthermore, in order to reach 80% of the theoretical efficacy, a molar ratio of 20:1, or 12mL of 20wt.% sodium hydroxide solution per gram of silicon, would be required. These results suggest that the actual gravimetric hydrogen storage capacity is less than 1%, casting doubts as to whether the use of silicon for hydrogen generation in real systems would be possible
An optimization tool to design the field of a solar power tower plant allowing heliostats of different sizes

The design of a Solar Power Tower plant involves the optimization of the
heliostat field layout. Fields are usually designed to have all heliostats of identical size. Although the use of a single heliostat size has been questioned in the literature, there are no tools to design fields with heliostats of several sizes at the same time. In this paper, the problem of optimizing the heliostat field layout of a system with heliostats of different sizes is addressed. We present an optimization tool to design solar plants allowing two heliostat sizes. The methodology is illustrated with a particular example considering different heliostat costs.Ministerio de Economía y CompetitividadJunta de AndalucíaGobierno VascoUnión Europe
Elucidating the process of hydrogen generation from the reaction of sodium hydroxide solution and ferrosilicon

This is an Open Access Article. It is published by Wiley under the Creative Commons Attribution 4.0 Unported Licence (CC BY). Full details of this licence are available at: http://creativecommons.org/licenses/by/4.0/For the first time, the process of hydrogen evolution from ferrosilicon 75 using sodium hydroxide solution has been investigated as a function of temperature using a combination of X-ray photoelectron spectroscopy, X-ray diffraction and physical measurements. Ferrosilicon 75, a mixture of silicon (~50wt.%) and iron disilicide (~50wt.%), has been shown to produce hydrogen by the action of sodium hydroxide solution on the silicon only, with the iron disilicide acting in the role of spectator/protector species for the silicon. Neither iron disilicide alone nor ferrosilicon 45, which does not contain a pure metallic silicon phase, was found to generate hydrogen under similar reaction conditions, further indicating that the presence of a pure metallic silicon phase is essential for hydrogen generation. As the iron disilicide acts as a diluent for the active silicon, it is hypothesized that this would result in a slower release of hydrogen than that which would be obtained from the reaction of silicon alone, which may be useful for applications which require a long-term, sustained release of hydrogen. A hydrogen yield of 462.5mL/g and a maximum hydrogen generation rate of 83mL/min g were obtained within 10min of reaction with 40wt.%\ud
NaOH at 348K
Simulation analysis of cooling methods of an on-board organic Rankine cycle exhaust heat recovery system

Energy saving and emission reduction of engines were taken seriously, especially for vehicular diesel engines.\ud
Exhaust heat recovery based on organic Rankine cycle (ORC) system has been considered as an effective\ud
approach for improving engine fuel economy. This article presents the investigation of water or air cooling\ud
method for an ORC exhaust heat recovery system on a heavy duty truck through simulations. The models of\ud
the truck engine and the ORC system were developed in GT-suite, and the integration system model was\ud
developed in the Simulink environment. The validity of the models was verified experimentally. The\ud
performance of the vehicular engine with ORC system using water or air cooling method was comparatively\ud
analyzed. The simulation results indicated that water cooling method is more suitable for the vehicular ORC\ud
system than air cooling method. The relation between benefit and penalty of the ORC system and cooling system\ud
was discussed. The operating condition of the cooling system was confirmed having significant effects on the\ud
combined system performance, especially the fan speed. The performance improvement of the engine with the\ud
use of ORC system was further evaluated under different engine operating conditions and ambient temperatures.\ud
Lower ambient temperature had positive impacts on the engine fuel economy. The mass flow rate of exhaust\ud
gas for heat recovery should be regulated for better performance under high ambient temperature
Stability evaluation of ethanol dry reforming on Lanthania‐doped cobalt‐based catalysts for hydrogen‐rich syngas generation

Catalytic stability with time‐on‐stream is an important aspect in ethanol dry reforming (EDR) since catalysts could encounter undesirable deterioration arising from deposited carbon. This work examined the promotional effect of La on 10%Co/Al2O3 in terms of activity, stability, and characteristics. Catalysts were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman, and X‐ray photoelectron spectroscopy (XPS) measurements whilst catalytic EDR performance of La‐promoted and unpromoted 10%Co/Al2O3 prepared via wet impregnation technique was investigated at 973 K for 72 h using a stoichiometric feed ratio (C2H5OH/CO2 = 1/1). La promoter substantially enhanced both metal dispersion and metal surface area from 0.11% to 0.64% and 0.08 to 0.43 m2 g−1, respectively. Ethanol and CO2 conversions appeared to be stable within 50 to 72 h after experiencing an initial activity drop. The conversion of C2H5OH and CO2 for La‐promoted catalyst was about 1.65 and 1.34 times greater than unpromoted counterpart in this order. The carbonaceous deposition was considerably decreased from 55.6% to 36.8% with La promotion due to La2O2CO3 intermediate formation. Additionally, 3%La‐10%Co/Al2O3 possessed greater oxygen vacancies acting as active sites for CO2adsorption and hence increasing carbon gasification. Even though graphitic and filamentous carbons were formed on used catalyst surface, La‐addition diminished graphite formation and increased the reactiveness of amorphous carbon
Becoming 'whole' again: A qualitative study of women's views of recovering from anorexia nervosa

This study explored how women made sense of their recovery from Anorexia Nervosa (AN). Semi-structured telephone interviews were carried out with fifteen women who had received a diagnosis of AN and defined themselves as either recovered or in recovery. Data were analysed using interpretative phenomenological analysis (IPA). The women described their experiences in terms of three broad areas; being anorexic; the process of change; and being recovered. Transcending these themes was a series of dichotomies involving splits between their mind and body, AN behaviour and cognitions and their rational and irrational side. Further, they indicated that recovery reflects the time when these many different components of their selves are no longer divided and that this was often facilitated through therapy and close relationships which enabled them to find non bodily means to express their distress. Therapy should therefore aim to facilitate a sense of becoming 'whole' again. © 2011 John Wiley & Sons, Ltd and Eating Disorders Association
Compulsive exercise and eating disorders

This is the pre-peer reviewed version of the following\ud
article: MEYER, C. ... et al, 2011. Compulsive exercise and eating disorders. European Eating Disorders Review, 19 (3), pp. 174 - 189,\ud
which has been published in final form at: http://dx.doi.org/10.1002/erv.1122The aim of this review was to develop an empirically supported cognitive behavioural model of compulsive exercise within the context of the eating disorders. A systematic review of the correlates and predictors of compulsive exercise among eating disordered patients identified four key correlates. These were subsequently validated by a second review, incorporating both the clinical and non-clinical as well as the exercise science literatures. A proposed model is presented which is both evidence-based and testabl
The meaning of food (MOF): The development of a new measurement tool

This paper aimed to develop a reliable measurement tool to evaluate the meanings of food that could be used in both practice and research and to examine possible gender differences. A new meaning of food questionnaire (MOF) was refined across two studies (study 1, n = 451 and study 2, n = 170). The final questionnaire consisted of 25 items and 8 reliable subscales: food and sex, emotional regulation, treat, guilt, social interaction, control over life, control over food, family. The new Meaning of Food (MOF) questionnaire could be used in both research and clinical practice to profile patients and explore predictors of eating behaviour. Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association
Prevalence of eating disorders amongst dancers: a systemic review and meta-analysis

This is the pre-peer reviewed version of the following article: ARCELUS, J., WITCOMB, G.L. and MITCHELL, A., 2014. Prevalence of eating disorders amongst dancers: a systemic review and meta-analysis. European Eating Disorders Review, 22 (2), pp. 92 - 101, which has been published in final form at http://dx.doi.org/10.1002/erv.2271. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Eating disorders in dancers are thought to be common, but the exact rates remain to be clariﬁed. The aim of this study is to systematically\ud
compile and analyse the rates of eating disorde rs in dancers. A literature search, appraisal and meta-analysis were conducted. Thi rty-three\ud
relevant studies were published between 1966 and 2013 with sufﬁcient data for extraction. Primary data were extracted as raw numbers\ud
or conﬁdence intervals. Risk ratios and 95% conﬁdence intervals were calculated for controlled studies. The overall prevalence of eating\ud
disorders was 12.0% (16.4% for ballet dancers), 2.0% (4% for bal let dancers) for anorexia, 4.4% (2% for ballet dancers) for bulimia and\ud
9.5% (14.9% for ballet dancers) for eating disorders not otherwise speciﬁed (EDNOS). The dancer group had higher mean scores on the\ud
EAT-26 and the Eating Disorder Inventory subscales. Dancers, in general, had a higher risk of suffering from eating disorders in general,\ud
anorexia nervosa and EDNOS, but no higher risk of suffering from bulimia nervosa. The study concluded that as dancers had a three\ud
times higher risk of suffering from eating disorders, particularly anorexia nervosa and EDNOS, speciﬁcally designed services for this\ud
population should be considere
Sociocultural risk factors for compulsive exercise: a prospective study of adolescents

This is the peer reviewed version of the following article: GOODWIN, H., HAYCRAFT, E. and MEYER, C., 2014. Sociocultural risk factors for compulsive exercise: a prospective study of adolescents.  European Eating Disorders Review, 22(5), pp.360-365, which has been published in final form at http://dx.doi.org/10.1002/erv.2309 This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.The risk factors for compulsive exercise are unknown. This study aims to explore longitudinal sociocultural risk factors for compulsive\ud
exercise, using a 12-month prospective design. A sample of 332 male and female adolescents (aged 13–15 years at baseline) completed\ud
self-report measures of sociocultural risk factors and compulsive exercise at baseline and eating disorder psychopathology and compulsive\ud
exercise at 12-month follow-up assessment. Hierarchical regressions found that family and peer messages to become more muscular\ud
predicted compulsive exercise in boys, whereas feeling pressure from the media to be thin was a significant predictor of compulsive\ud
exercise in girls. These relationships remained significant when controlling for eating disorder psychopathology but became nonsignificant\ud
when initial levels of compulsive exercise were entered into the model. The findings suggest that sociocultural risk factors may contribute\ud
to the development of compulsive exercise but future research should utilise a younger sample and employ a longer follow-up\ud
period to identify true longitudinal effects. Copyright © 2014 John Wiley & Sons, Ltd and Eating Disorders Association
Activity-related parenting practices: development of the parenting related to activity measure (PRAM) and links with mothers' eating psychopathology and compulsive exercise beliefs

This is the accepted version of the following article: Haycraft, E., Powell, F., and Meyer, C., 2014. Activity-Related Parenting Practices: Development of the Parenting Related to Activity Measure (PRAM) and Links with Mothers' Eating Psychopathology and Compulsive Exercise Beliefs, Eur. Eat. Disorders Rev., 23; pp. 51–61, which has been published in final form at http://dx.doi.org/10.1002/erv.2331This is a two-study paper that developed a measure to assess parenting practices related to children's physical activity and explored maternal predictors of such parenting practices. Study 1: A self-report measure of parents' activity-related practices (the Parenting Related to Activity Measure) was developed, and a principal component analysis was carried out using data from 233 mothers of 4.5- to 9-year-old children. The results supported a six-factor model and yielded the following subscales: Responsibility/monitoring; Activity regulation; Control of active behaviours; Overweight concern; Rewarding parenting; and Pressure to exercise. Study 2: Mothers (N = 170) completed the Parenting Related to Activity Measure, alongside measures of eating psychopathology and compulsive exercise, to identify predictors of activity-related parenting practices. Mothers' eating psychopathology and exercise beliefs predicted activity parenting practices with their sons and daughters, but different predictors were seen for mothers of daughters versus sons. Mothers' eating and exercise attitudes are important predictors of their activity-related parenting practices, particularly with girls. Identifying early interactions around activity/exercise could be important in preventing the development of problematic beliefs about exercise, which are often a key symptom of eating disorders