Considering the application of the polymer electrolyte membrane fuel cell (PEMFC), the separator thickness plays a significant role in determining the weight, volume, and costs of the PEMFC. In addition, thermal management, i.e., temperature distribution is also important for the PEMFC system to obtain higher performance. However, there were few reports investigating the relation between the temperature profile and the power generation characteristics e.g., the current density distribution of PEMFC operated at higher temperatures (HT-PEMFC). This paper aims to study the impact of separator thickness on the temperature profile and the current density profile of HT-PEMFC. The impact of separator thickness on the gases i.e., H2, O2 profile of HT-PEMFC numerically was also studied using CFD software COMSOL Multiphysics in the paper. In the study, the operating temperature and the relative humidity (RH) of the supply gas were varied with the separator thickness of 2.0 mm, 1.5 mm, and 1.0 mm, respectively. The study revealed that the optimum thickness was 2.0 mm to realize higher power generation of HT-PEMFC. The heat capacity of the separator thickness of 2.0 mm was the biggest among the separators investigated in this study, resulting in the dry-up of PEM and catalyst layer was lower compared to the thinner separator thickness. It also clarified the effects of separator thickness of profile gases, e.g., O2, H2O, and current density profile became larger under the higher temperature and the lower RH conditions.
The analysis of the accumulation and export of nutrients by the cowpea crop is fundamental for a more sustainable fertilization program, because the definition of the doses of organic fertilizers based only on the estimated maximum yield does not guarantee the maintenance of soil fertility. The objective of this study was to evaluate the effect of fertilization with chicken manure on the productivity, accumulation and exportation of nutrients by the pods of cowpea. A randomized block design was used, with five doses of chicken manure (0; 5; 10; 20 and 40 t ha-1) and four repetitions. The highest levels of P and Mg were found in the leaves with the application of 40 t ha-1 of manure. The maximum pod length was 14.47 cm, estimated with the dose of 33.33 t ha-1 of manure. The highest values of diameter, number of pods per plant and pod productivity were observed at the highest dose of manure applied. In relative terms, that is, total exported in relation to the total extracted by the aerial part, phosphorus is the nutrient most exported by the pods, on average 58%, followed by N (55%), K (43%), Mg (40%), S (38%) and Ca (17%). At the highest dose, although Ca accumulation occurred in large quantities (31.3 kg ha-1), only 13% of it was exported by the pods. Fertilizing cowpea with chicken manure supplied essential nutrients and increased pod yield from 7.2 (no fertilization) to 16.3 t ha-1 (fertilization with 40 t ha-1 of chicken manure). The plant remains of the cowpea constitute an important source of nutrients, being obtained at the highest dose of manure applied (40 t ha-1) the following amounts of macronutrients (kg ha-1): N (51.4); P (5.1); K (27.6); Ca (27.1); Mg (8.2); S (5.1), which may return to the soil, with the incorporation of the plants.
In this paper, a detailed mineralogical and genesis investigation have been carried out in the seven locations of the Iron Ore in Hazara area. Thick bedded iron ore have been observed between Kawagarh Formation and Hangu Formation i.e., Cretaceous-Paleocene boundary. At the base of Hangu Formation, variable thickness of these lateritic beds spread throughout the Hazara and Kohat-Potwar plateau. This hematite ore exists in the form of unconformity. X-ray diffraction technique (XRD), X-ray fluorescence spectrometry (XRF), detailed petroghraphic study and scanning electron microscope (SEM) techniques indicated that those iron bears minerals including hematite, chamosite and quartz, albite, clinochlore, illite-montmorillonite, kaolinite, calcite, dolomite, whereas ankerite are the impurities present in these beds. The X-ray fluorescence (XRF) results show that the total Fe2O3 ranges from 39 to 56%, with high silica and alumina ratio of less than one. Beneficiation requires for significant increase in ore grade. The petroghraphic study revealed the presence of ooids fragments as nuclei of other ooids with limited clastic supply, which indicate high energy shallow marine depositional setting under warm and humid climate. The overall results show that Langrial Iron Ore is a low-grade iron ore which can be upgraded up to 62% by applying modern mining techniques so as to fulfill steel requirements of the country.
This paper explores the ritual practices associated with Beiyuan Tribute Tea production in Jianzhou, Fujian, China. Beiyuan Tribute Tea, a historically significant tea, originated in the Tang Dynasty, flourished during the Song Dynasty, and experienced a decline in the Ming Dynasty, reproduced in contemporary times. The tea’s production involved intricate rituals that not only enhanced its quality but also embedded it deeply into the socio-cultural and religious fabric of the time. These rituals, encompassing aspects of religious reverence, craftsmanship, and social etiquette, played a crucial role in the tea’s esteemed status as a tribute to Chinese emperors in history. The study utilized ethnographic methods, including participant observation, in-depth interviews with 17 people, and document analysis, to capture the rich, contextual details of the tea production process. The study delves into the historical context, production techniques, and symbolic meanings of the rituals, highlighting their impact on the broader cultural heritage of Chinese tea. The recent revival efforts of these traditions underscore their enduring significance and offer insights into the cultural continuity and adaptation in contemporary tea practices.
This study investigates the impact of toll road construction on 59 micro, small, and medium enterprises in Kampar, Pekanbaru, and Dumai cities. The research aims to analyze the economic and environmental effects of infrastructure expansion on businesses’ profitability and sustainability, providing insights for policymakers and stakeholders to develop mitigation strategies to support MSMEs amidst ongoing infrastructure development. Structural equation modeling, spatial environmental impact analysis, and qualitative data analysis using five-level qualitative data analysis (FL-QDA) were all used together in a mixed-methods approach. Data collection involved observations, interviews, questionnaires, and geospatial analysis, including the use of a Geo-Information System (GIS) supported by drone reconnaissance to map affected areas. The study revealed that the toll roads significantly enhanced connectivity and economic growth but also negatively impacted local economies (β = 0.32, R2 = 0.60, P-value ≤ 0.05). and the environment (β = 0.34, P-value ≤ 0.05), as 49% of respondents experienced a 50% decrease in profitability. To mitigate the risk of impact, policymakers should prioritize the principle of prudence to evaluate the significance of mitigation policy implementation (β = 0.144, P-value ≥ 0.05). In a nutshell, toll road construction significantly impacts MSMEs’ business continuity, necessitating an innovative strategy involving monitoring and participatory approaches to mitigate risk.
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