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Abstract Carbon-based counter electrodes of dye-sensitized solar cells (DSSCs) such as carbon black-graphite composite (CB/Gr) have received unprecedented interest in recent years due to their ease of fabrication, good corrosion resistance, and low cost compared to platinum (Pt) electrodes. However, the poor surface adherence between the carbon counter electrodes (CE) and FTO substrate, low surface area, and poor inter-particle connection between the carbon materials have consistently become a major challenge. In order to overcome these issues, we have fabricated CB/Gr by incorporating binders of titanium (IV) isopropoxide (TTIP), and zirconium (IV) dioxide (ZrO2) as the counter electrodes for the DSSC. The performance of the CE is characterized by four-point probe conductivity measurement, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and current density voltage (J-V) characteristics. The results revealed that incorporating binders to the CB/Gr has improved the series resistance (RS) and charge transfer resistance (RCT), which enhances the short-circuit current density (JSC), fill factor (FF), and the power conversion efficiency (PCE) of the device. The TTIP binder in CB/Gr CE exhibited superior performance in DSSC is largely attributed to the formation of TiO2 in situ with small particle size of about 100 nm, leading to enhanced intimate contact between the carbon materials, high surface area, and better surface adherence between counter electrode and the FTO substrate. Our findings, thereby, offer the possibility to engineer and optimize the energy levels of CE in an effort to develop a high-performing DSSC counter electrode.

This paper proposes a novel 3D micro-siting approach for optimal placement of wind turbines in the continuous space of a wind farm. Along with X and Y positions, hub height and rotor radius of each turbine is optimized to maximize the yield of the farm. Such 3D siting not only reduces the land requirement, but also extracts more power from the same site. Proposed 3D siting problem is formulated as a constrained optimization problem and solved by a particle swarm optimization (PSO) algorithm.

Brunei Darussalam has the highest electricity consumption per capita among Southeast Asian countries. This high electricity consumption dramatically contributes to environmental issues because gas is the primary source of energy generation in Brunei. Hence, the government must come up with measures to counter the issues. However, before providing solutions, it is also vital to understand electricity consumption behaviour, especially in the residential sector. The residential sector in Brunei has the second highest electricity consumption, and the government heavily subsidizes it. This paper aims to study the residential load profiles in Brunei based on the locations of the households and the total monthly incomes per household. The data for this study was obtained through an online questionnaire to calculate household electrical appliance usage patterns. The result of the study shows that the residential load profiles are almost the same despite the different locations and salaries of the households. However, upon looking at the total daily consumption, Temburong has minor electricity consumption of 50 kWh, while the rest uses about 80 kWh daily. Also, the study showed that the higher the income, the higher the electricity consumption of the households. Lastly, air-conditioning shows the highest daily electricity consumption, more than 50% of the total usage.

Professionals in industries are making progress in creating predictive techniques for evaluating critical characteristics and reactions of engineered materials. The objective of this investigation is to determine the optimal settings for a 3D printer made of acrylonitrile butadiene styrene (ABS) in terms of its conflicting responses (flexural strength (FS), tensile strength (TS), average surface roughness (Ra), print time (T), and energy consumption (E)). Layer thickness (LT), printing speed (PS), and infill density (ID) are all quantifiable characteristics that were chosen. For the experimental methods of the prediction models, twenty samples were created using a full central composite design (CCD). The models were verified by proving that the experimental results were consistent with the predictions using validation trial tests, and the significance of the performance parameters was confirmed using analysis of variance (ANOVA). The most crucial element in obtaining the desired Ra and T was LT, whereas ID was the most crucial in attaining the desired mechanical characteristics. Numerical multi-objective optimization was used to achieve the following parameters: LT = 0.27 mm, ID = 84 percent, and PS = 51.1 mm/s; FS = 58.01 MPa; TS = 35.8 MPa; lowest Ra = 8.01 m; lowest T = 58 min; and E = 0.21 kwh. Manufacturers and practitioners may profit from using the produced numerically optimized model to forecast the necessary surface quality for different aspects before undertaking trials.

A microchannel reactor improves the overall mass and heat transfer as compared with a conventional reactor. This is attributed to the creation of a high area-to-volume ratio and enhanced mixing due to the presence of the vortices inside the slug. In this paper, the mass-transfer performance was studied using a cross-junction microchannel. Subsequently, the computational fluid dynamic (CFD) method was used to observe the oil concentration contour inside a slug using volume-of-fluid (VOF) with the species-transport model. Based on the simulation results, the oil concentration was accumulated in both the slug’s rear and front regions. Hence, the creation of four vortices resulted in the creation of dead zones at the low-oil-concentration region. Furthermore, it has been observed that an optimum flow rate in a microchannel reactor is required to achieve a high mass transfer. A higher oil concentration was measured during the slug formation at a low flow regime due to the long residence time. In contrast, a high mass transfer has been reported during the slug-moving stage due to the higher vortices velocity, resulting in enhanced mixing and mass transfer. Hence, slug forming and the moving stage substantially influenced mass transfer at low and high flow rates, respectively.

La réalisation des objectifs de développement durable (ODD) nécessite d'équilibrer les demandes en terres entre l'agriculture (ODD 2) et la biodiversité (ODD 15).La production d'huiles végétales, et en particulier d'huile de palme, illustre ces demandes concurrentes et ces compromis.L' huile de palme représente ~40 % de la demande annuelle mondiale actuelle d'huile végétale pour l'alimentation humaine, animale et pour le carburant (210 millions de tonnes (Mt)), mais le palmier à huile planté couvre moins de 5 à 5,5 % de la superficie totale des cultures oléagineuses mondiales (environ 425 Mha), en raison des rendements relativement élevés du palmier à huile.L' expansion récente du palmier à huile dans les régions boisées de Bornéo, de Sumatra et de la péninsule malaise, où plus de 90 % de l'huile de palme mondiale est produite, a suscité de vives inquiétudes quant au rôle du palmier à huile dans la déforestation.La contribution directe de l'expansion du palmier à huile à la déforestation tropicale régionale varie considérablement, allant de 3 % en Afrique de l'Ouest à 47 % en Malaisie.Le palmier à huile est également impliqué dans le drainage et la combustion des tourbières en Asie du Sud-Est.Les impacts environnementaux négatifs documentés d'une telle expansion comprennent le déclin de la biodiversité, les émissions de gaz à effet de serre et la pollution atmosphérique.Toutefois, le palmier à huile produit généralement plus l'huile par superficie par rapport aux autres cultures oléagineuses, est souvent économiquement viable sur des sites inadaptés à la plupart des autres cultures, et génère une richesse considérable pour au moins certains acteurs. La demande mondiale d'huiles végétales devrait augmenter de 46 % d'ici 2050. Répondre à cette demande par une expansion supplémentaire du palmier à huile par rapport à d'autres cultures d'huile végétale entraînera des effets différentiels substantiels sur la biodiversité, la sécurité alimentaire, le changement climatique, la dégradation des terres et les moyens de subsistance. Notre examen souligne que, bien que des lacunes importantes subsistent dans notre compréhension de la relation entre les impacts environnementaux, socioculturels et économiques du palmier à huile, et la portée, la rigueur et l'efficacité des initiatives visant à y remédier, il y a eu peu de recherches sur les impacts et les compromis des autres cultures d'huile végétale. Une plus grande attention de la recherche doit être accordée à l'étude des impacts de la production d'huile de palme par rapport aux alternatives pour les compromis à évaluer à l'échelle mondiale. El cumplimiento de los Objetivos de Desarrollo Sostenible (ODS) requiere equilibrar las demandas de tierras entre la agricultura (ODS 2) y la biodiversidad (ODS 15). La producción de aceites vegetales, y en particular el aceite de palma, ilustra estas demandas y compensaciones competitivas. El aceite de palma representa aproximadamente el 40% de la demanda anual mundial actual de aceite vegetal como alimento, pienso y combustible (210 millones de toneladas (Mt)), pero la palma aceitera plantada cubre menos del 5-5,5% del área total de cultivos oleaginosos mundiales (aprox. 425 Mha). debido a los rendimientos relativamente altos de la palma aceitera. La reciente expansión de la palma aceitera en las regiones boscosas de Borneo, Sumatra y la Península Malaya, donde se produce más del 90% del aceite de palma mundial, ha generado una preocupación sustancial sobre el papel de la palma aceitera en la deforestación. La contribución directa de la expansión de la palma aceitera a la deforestación tropical regional varía ampliamente, desde el 3% en África occidental hasta el 47% en Malasia. La palma aceitera también está implicada en el drenaje y la quema de turberas en el sudeste asiático. Los impactos ambientales negativos documentados de dicha expansión incluyen la disminución de la biodiversidad, las emisiones de gases de efecto invernadero y la contaminación del aire. Sin embargo, la palma aceitera generalmente produce más. aceite por área que otros cultivos oleaginosos, a menudo es económicamente viable en sitios inadecuados para la mayoría de los otros cultivos y genera una riqueza considerable para al menos algunos actores. Se proyecta que la demanda mundial de aceites vegetales aumentará en un 46% para 2050. Satisfacer esta demanda a través de una expansión adicional de la palma aceitera frente a otros cultivos de aceite vegetal conducirá a efectos diferenciales sustanciales en la biodiversidad, la seguridad alimentaria, el cambio climático, la degradación de la tierra y los medios de vida. Nuestra revisión destaca que, aunque quedan brechas sustanciales en nuestra comprensión de la relación entre los impactos ambientales, socioculturales y económicos de la palma aceitera, y el alcance, la rigurosidad y la efectividad de las iniciativas para abordarlos, ha habido poca investigación sobre los impactos y las compensaciones de otros cultivos de aceite vegetal. Se debe prestar mayor atención a la investigación para investigar los impactos de la producción de aceite de palma en comparación con las alternativas para las compensaciones que se evaluarán a escala mundial. Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15).The production of vegetable oils, and in particular palm oil, illustrates these competing demands and trade-offs.Palm oil accounts for ~40% of the current global annual demand for vegetable oil as food, animal feed, and fuel (210 million tons (Mt)), but planted oil palm covers less than 5-5.5% of the total global oil crop area (ca.425 Mha), due to oil palm's relatively high yields.Recent oil palm expansion in forested regions of Borneo, Sumatra, and the Malay Peninsula, where >90% of global palm oil is produced, has led to substantial concern around oil palm's role in deforestation.Oil palm expansion's direct contribution to regional tropical deforestation varies widely, ranging from 3% in West Africa to 47% in Malaysia.Oil palm is also implicated in peatland draining and burning in Southeast Asia.Documented negative environmental impacts from such expansion include biodiversity declines, greenhouse gas emissions, and air pollution.However, oil palm generally produces more oil per area than other oil crops, is often economically viable in sites unsuitable for most other crops, and generates considerable wealth for at least some actors.Global demand for vegetable oils is projected to increase by 46% by 2050.Meeting this demand through additional expansion of oil palm versus other vegetable oil crops will lead to substantial differential effects on biodiversity, food security, climate change, land degradation, and livelihoods.Our review highlights that, although substantial gaps remain in our understanding of the relationship between the environmental, socio-cultural and economic impacts of oil palm, and the scope, stringency and effectiveness of initiatives to address these, there has been little research into the impacts and trade-offs of other vegetable oil crops.Greater research attention needs to be given to investigating the impacts of palm oil production compared to alternatives for the trade-offs to be assessed at a global scale. يتطلب تحقيق أهداف التنمية المستدامة (SDGs) موازنة الطلب على الأراضي بين الزراعة (SDG 2) والتنوع البيولوجي (SDG 15). يوضح إنتاج الزيوت النباتية، ولا سيما زيت النخيل، هذه المطالب والمقايضات المتنافسة. يمثل زيت النخيل حوالي40 ٪ من الطلب السنوي العالمي الحالي على الزيوت النباتية كغذاء وعلف حيواني ووقود (210 مليون طن متري)، لكن نخيل الزيت المزروع يغطي أقل من 5-5.5 ٪ من إجمالي مساحة محصول النفط العالمي (حوالي 425 مليون هكتار)، بسبب غلة نخيل الزيت المرتفعة نسبيًا. أدى التوسع الأخير في نخيل الزيت في مناطق الغابات في بورنيو وسومطرة وشبه جزيرة الملايو، حيث يتم إنتاج أكثر من 90 ٪ من زيت النخيل العالمي، إلى قلق كبير حول دور نخيل الزيت في إزالة الغابات. تختلف المساهمة المباشرة لتوسع نخيل الزيت في إزالة الغابات الاستوائية الإقليمية اختلافًا كبيرًا، حيث تتراوح من 3 ٪ في غرب إفريقيا إلى 47 ٪ في ماليزيا. كما يتورط نخيل الزيت في تصريف الأراضي الخثية وحرقها في جنوب شرق آسيا. وتشمل الآثار البيئية السلبية الموثقة من هذا التوسع انخفاض التنوع البيولوجي وانبعاثات غازات الدفيئة وتلوث الهواء. ومع ذلك، ينتج نخيل الزيت عمومًا المزيد من المتوقع أن يزداد الطلب العالمي على الزيوت النباتية بنسبة 46 ٪ بحلول عام 2050. وستؤدي تلبية هذا الطلب من خلال التوسع الإضافي في محاصيل نخيل الزيت مقابل محاصيل الزيوت النباتية الأخرى إلى آثار تفاضلية كبيرة على التنوع البيولوجي والأمن الغذائي وتغير المناخ وتدهور الأراضي وسبل العيش. وتسلط مراجعتنا الضوء على أنه على الرغم من استمرار وجود فجوات كبيرة في فهمنا للعلاقة بين الآثار البيئية والاجتماعية والثقافية والاقتصادية لنخيل الزيت، ونطاق وصرامة وفعالية المبادرات الرامية إلى معالجتها، إلا أنه لم يتم إجراء سوى القليل من الأبحاث حول تأثيرات ومقايضات محاصيل الزيوت النباتية الأخرى. ويلزم إيلاء اهتمام بحثي أكبر للتحقيق في آثار إنتاج زيت النخيل مقارنة ببدائل المقايضات التي سيتم تقييمها على نطاق عالمي.