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In a study of the electrochemical behavior of low-cyanide silver plating baths and of the properties of the deposits obtained, it was found that the current-potential curve obtained with a solid electrode showed a two-step reduction wave, the height of the first being 1/5 that of the second. Analysis of the results of polarographic and rotating disk electrode measurmenents sugests that the rate-controlling steps wereAgCN+e-_??_Ag+CN-……(1)Ag(CN)2-+e-_??_Ag+2CN-……(2)for the first and second waves respectively. The Tafel plots of the two waves showed linear relationships at their rising portions, and the reactions are accordingly concluded to be slow chargetransfer controlled.In baths to which selenocyanate ion was added, the increase in current was markedly greater for the second wave than for the first, and the wave was shifted to the positive side. Potential decay curves for the baths containing selenocyanate ion obtained by the current interrupter method showed lower differential capacities than those for baths that were free of selenocyanate ion. This indicates that the selenocyanate ions were adsorbed preferentially at the electrode, suppress the adsorption of cyanide ions and enhancing the silver deposition reaction.Deposits obtained by jet plating were matt at current densities lower than 50A/dm2, and their appearance was not affected by the addition of selenocyanate ion. At above 50A/dm2, deposits obtained from selenocyanate-free baths were burnt, but deposits obtained from baths with selenocyanate ion added were mirror-bright with a strong (200) orientation up to around 150A/dm2.

AbstractRecently, modern power systems depend heavily on MicroGrids (MGs), which can accommodate Distributed Energy Resources (DERs) economically and with high flexibility. MGs integrated with DERs can assist in enhancing energy security, significant cost savings, and reduction in emission of greenhouse gases. In this paper, the assessment of operating performance of proposed MG system with DERs is employed to investigate the multi‐objective problems of cost optimization and economic scheduling. A grid‐connected Micro‐grid (MG) combined with solar photovoltaic (PV), wind turbine (WT), fuel cell (FC), and Battery Energy Storage System (BESS) is implemented to model the problem. This proposed model is considered as a test system for cost optimization and battery charging/discharging optimization. The developed framework is presented as multi‐objective function with constraints that can be tackled using an effective optimization technique. The above stochastic multi‐objective problem is optimized using various commonly used Physics based Meta‐heuristic techniques such as Simulated Annealing (SA), Harmony Search (HS), Slime Mold Algorithm (SMA), Gravitational Search Algorithm (GSA), Black Hole Optimization (BHO), Sine Cosine Algorithm (SCA), Multiverse optimization (MVO) and Lightning Search Algorithm (LSA). The assessment of the aforementioned physics‐based optimization techniques used on the proposed MG test system is compared using the results. According to the analysis, Black Hole Optimization (BHO) and Lightning Search Algorithm (LSA) both provide greater cost savings overall and for battery charging, respectively. The suggested optimization methods will take the BESS charging/discharging pattern and total cost savings into account.

AbstractIn the present study, effect of internals and other hydrodynamic variables on pressure drop and expansion ratio were examined. The parameters studied include inlet air flow rate, bed height, spacing of internal, column diameter and percentage open area. Disc promoters of three different percentages of open area (48.03%, 55.15%, 66.26%) were used. The pressure drop was found to increase significantly with increase in bed height and decrease with open area of internals. As the spacing was decreased, the pressure drop increased first and then decreased due to effective breaking of bubbles in the presence of internals. The expansion ratio was seen to decrease significantly with decrease in the internal spacing and decrease in open area of internals. Correlations for pressure drop and expansion ratio have been found using dimensional analysis. The calculated values of pressure drop and expansion ratio were compared with experimental values. Several models have been developed using the Artificial Neural...

Cette étude examine les caractéristiques des profils de vitesse, de champ thermique et d'entropie pour l'écoulement de nanofluides hybrides traversant une feuille d'amidonnage avec un rayonnement thermique. Les nanotubes de carbone (SWCNT et MWCNT) sont utilisés comme nanoparticules avec flux de chaleur Cattaneo-Christov (CC). L'éthylène glycol est utilisé comme fluide de base dans ce cas. Pour obtenir une solution améliorée, l'écoulement de fluide sur les propriétés géométriques est conçu en utilisant des PDE hautement non linéaires, et les équations gouvernantes doivent être converties en systèmes d'équations non similaires sans dimension en utilisant le schéma de Keller-box bien connu et très efficace dans le logiciel de calcul Matlab. La faisabilité pratique de ces solutions est déterminée par la plage des paramètres de contrôle. La distribution de vitesse diminue à mesure que l'estimation des paramètres magnétiques augmente, cependant, le champ de température et la production d'entropie augmentent à mesure que la fluctuation des paramètres magnétiques diminue. Au fur et à mesure que le paramètre de glissement augmente, le champ de vitesse diminue. Le champ thermique est amélioré pour augmenter le paramètre de rayonnement, et le profil d'entropie est renforcé pour augmenter les valeurs des paramètres de Brinkman. Les résultats de cette recherche pourraient avoir un impact significatif sur les industries où le refroidissement et le chauffage locaux par jets d'impact sont nécessaires dans les appareils électroniques, les dissipateurs thermiques, les technologies de séchage, etc. À la connaissance des auteurs, il s'agit du premier effort visant à utiliser un nanofluide hybride pour analyser la formation d'entropie due au flux magnétohydrodynamique sur une feuille d'amidonnage. Este estudio examina las características de los perfiles de velocidad, campo térmico y entropía para el flujo híbrido de nanofluidos que pasa a través de una lámina de almidón con radiación térmica. Los nanotubos de carbono (SWCNT y MWCNT) se utilizan como nanopartículas con flujo de calor Cattaneo-Christov (CC). El etilenglicol se utiliza como fluido base en este caso. Para lograr una solución mejorada, el flujo de fluido sobre las propiedades geométricas se diseña utilizando PDE altamente no lineales, y las ecuaciones gobernantes deben convertirse en sistemas de ecuaciones no similares adimensionales utilizando el conocido esquema de Keller-box altamente eficiente en el software computacional MATLAB. La viabilidad práctica de estas soluciones está determinada por el rango de los parámetros de control. La distribución de velocidad se reduce a medida que aumenta la estimación del parámetro magnético, sin embargo, el campo de temperatura y la producción de entropía aumentan a medida que la fluctuación del parámetro magnético se aclara. A medida que aumenta el parámetro de deslizamiento, el campo de velocidad disminuye. El campo térmico se mejora para aumentar el parámetro de radiación, y el perfil de entropía se aumenta para aumentar los valores de los parámetros de Brinkman. Los hallazgos de esta investigación podrían tener un impacto significativo en las industrias donde se necesita refrigeración local y calefacción a través de chorros de choque en dispositivos electrónicos, disipadores de calor, tecnologías de secado, etc. Según el conocimiento de los autores, este es el primer esfuerzo para emplear un nanofluido híbrido para analizar la formación de entropía debido al flujo magnetohidrodinámico sobre una lámina de almidón. This study examines the characteristics of the velocity, thermal field and entropy profiles for hybrid nanofluid flow passing through a starching sheet with thermal radiation. The carbon nanotube (SWCNT and MWCNT) are used as a nanoparticles with Cattaneo-Christov (CC) heat flux. Ethylene glycol is utilized as a base fluid in this case. To achieve an improved solution, the fluid flow over the geometric properties is designed using highly non-linear PDEs, and the governing equations must be converted into dimensionless non-similar equation systems using the highly efficient well-known Keller-box scheme in computational software MATLAB. The practical feasibility of these solutions is determined by the range of the controlling parameters. The velocity distribution reduces as the magnetic parameter estimate increases, however, the temperature field and entropy production increase as the magnetic parameter fluctuation esclates. As the slip parameter is increased, the velocity field diminish. The thermal field is enhanced for rising the radiation parameter, and the entropy profile is boosted for increasing Brinkman parameter values. The findings of this research might have a significant impact on industries where local cooling and heating via impingement jets are needed in electronic devices, heat sinks, drying technologies, and so on. To the best of the authors' knowledge, this is the first effort to employ a hybrid nanofluid to analyze entropy formation due to magnetohydrodynamics flow over a starching sheet. تبحث هذه الدراسة في خصائص ملامح السرعة والحقل الحراري والانتروبيا لتدفق السوائل النانوية الهجينة التي تمر عبر ورقة النشا مع الإشعاع الحراري. يتم استخدام الأنبوب النانوي الكربوني (SWCNT و MWCNT) كجسيمات نانوية مع تدفق حراري Cattaneo - Christov (CC). يستخدم جلايكول الإيثيلين كسائل أساسي في هذه الحالة. لتحقيق حل محسّن، تم تصميم تدفق المائع عبر الخصائص الهندسية باستخدام PDEs غير خطية للغاية، ويجب تحويل المعادلات الحاكمة إلى أنظمة معادلات غير متشابهة بلا أبعاد باستخدام مخطط Keller - box المعروف عالي الكفاءة في البرنامج الحاسوبي MATLAB. يتم تحديد الجدوى العملية لهذه الحلول من خلال نطاق معلمات التحكم. ينخفض توزيع السرعة مع زيادة تقدير المعلمة المغناطيسية، ومع ذلك، يزداد مجال درجة الحرارة وإنتاج الإنتروبيا مع تذبذب المعلمة المغناطيسية. مع زيادة معامل الانزلاق، يتناقص مجال السرعة. يتم تعزيز المجال الحراري لرفع معلمة الإشعاع، ويتم تعزيز ملف تعريف الإنتروبيا لزيادة قيم معلمة برينكمان. قد يكون لنتائج هذا البحث تأثير كبير على الصناعات التي تحتاج إلى التبريد والتدفئة المحليين عبر نفاثات الاصطدام في الأجهزة الإلكترونية وأحواض الحرارة وتقنيات التجفيف وما إلى ذلك. على حد علم المؤلفين، هذا هو أول جهد لتوظيف مائع نانوي هجين لتحليل تكوين الإنتروبيا بسبب تدفق الديناميكا المائية المغناطيسية على ورقة النشا.

Large-size woody biomass is a valuable renewable resource to replace fossil fuels in biorefinery processes. The preprocessing of wood chips and briquettes is challenging to manage, especially in an industrial setting, as it generates a significant amount of dust and noise and occasionally causes unexpected accidents. As a result, a substantial amount of resources, energy, labor, and space are needed. The thermochemical conversion behavior of large-size woody biomass was studied to reduce energy consumption for chipping. Large-size wood was 1.5 m in length, 0.1 m in breadth, and stacked 90 cm in height. This strategy has many benefits, including increased effectiveness and reduced CO2 emissions. The target of this paper presents the thermochemical process, and large-size wood was chosen because it provides high-quality product gas while reducing the preprocessing fuel cost. This review examines the benefits of thermochemical conversion technologies for assessing the likelihood of carbon neutrality.

Energy conservation potential of the evaporative roof cooling technique for a cinema house in a composite climate (characterized by Delhi) has been evaluated. Thermal loads due to heat conduction through the building envelope, the required ventilation and the occupants have been taken into account. Life-cycle-cost analysis has been employed to evaluate the cost effectiveness of this energy conservation technique. It is seen that evaporative cooling on the roof leads to a net saving of 14% in the initial investment and 17% in the annual cost.

In this paper, we propose and discuss the challenges of a novel method for securing the readings of smart electricity meters against tampering or malfunctioning. We apply the idea of linear error-correcting block codes, which has originally been used in detecting and correcting errors in data transmission, to detect and correct customer attacks aimed at changing the readings of smart electricity meters. We propose to use these codes, with some modifications, in order to detect and correct deceptive readings of a group of electricity meters measuring the energy delivered by cables\feeders fed from the same node\bus. We start by considering a single meter attack, and we show that the detection and correction of a single attack in the readings of 2m — M — 1 meters, connected to cables fed from the same node, requires only using M current transformers in addition to knowing the voltage at the common node. We demonstrate the theoretical implementation of this coding scheme, and then we discuss some practical challenges and their proposed solutions. Furthermore, extension to multi-error correcting codes, which are capable of detecting and correcting several simultaneous deceptive readings of a group of meters, is also discussed.

Cooperative learning seems to be the right methodology to tackle the development of the teamwork competence inside the process of teaching?learning at the University. That strategy has been used by lecturers of different faculties and schools of the University of the Basque Country UPV/EHU who have sorted an Educational Team on cooperative learning. The experience was developed in six different groups which add up as 185 students. The outcome of that experience was analysed by means of a questionnaire which gathers the main competences of teamwork. The analysis of the dimensions of the questionnaire shows a structure with two dimensions: (1) 'interpersonal competences' and (2) 'instrumental competences'. Students seem to prioritise the most technical or procedural competences (instrumental) over personal and relationship competences (interpersonal) in their formative process and assessment of their learning.