Hydrogen fuel cell technology is now being researched extensively globally to provide a stable renewable energy source in the future. New research is aiding in improving performance, endurance, cost-efficiency, and the elimination of fuel cell limitations. Throughout the development process, the many aspects impacting the features, efficiency, durability, and cost of a fuel cell must be examined in a specific method. This review study looked at the impact of several variables on hydrogen fuel cell durability (HFC). In every sphere of fuel cell application, long-term operation is a must to make this electrochemical cell work. The major durability-enhancing aspects of a fuel cell include temperature, catalytic decay, contaminants, thermal energy and water maintenance, and fuel cell component design.

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Random copolymerizations of L-Lactide with ε-Caprolactone by ring opening polymerization reactions were carried out. A number of copolymers were formed and observed that any composition of copolymer can be formed by changing the feed ratio of the respective monomers. The effect of temperature and time in copolymerization reaction were studied. For their characterization, NMR, IR, DSC and GPC were measured. The stereo-effect of the lactic acid based biodegradable polymers and copolymers for improve thermo-mechanical properties were studied. The obtained copolymers also show stereo-effect like homopolymer. The biodegradability of obtained polymers, copolymers and stereocomplex were studied in three different biodegradation methods; e.g., Enzymatic method, Composting method and Activated Sludge treatment method; and compared to each other.

Rapid urbanization is not only an issue in plain areas but also in mountainous regions. However, urbanization affects the socio-ecological pattern of mountainous regions especially depleting natural resources, e.g., traditional agricultural practices. Although urban sprawl impinges on such fertile productive lands, it also positively affects trade activities, and high-income opportunities, and the region will have high spatial interaction. This paper presents the results of an attempt to gain insight into the mechanisms for the urban growth of district Chitral (Chitral Town) located in the Hindu Kush range north of KPK Pakistan. Over the last few decades, the urban agglomeration has become attractive among migrants from within and beyond the district, further accelerating urban growth in the surrounding area. The landscape transformation phenomenon in Chitral town was investigated with the following objectives: (i) Detection of spatiotemporal change in the study area over the last two decades, (ii) identification of existing landscape patterns i.e. land-use assessment by analysing the acquired high-resolution remote satellite imageries for the years 2003 and 2020, (iii) empirical analysis of data within the framework of an object-based approach. Land-use transformations like spatiotemporal change, loss of agriculture, and infrastructure patterns of urban growth were estimated for the past 17 years. This study revealed that the agricultural Land use has declined by 348 m2 while the Built-up area has increased by 318 m2. The research offers practical recommendations for sustainable town planning and management. As such, this study has the potential to propose future strategies and it may be helpful to the policy/decision-makers in the development of future town planning in the similar mountainous regions of Pakistan or elsewhere.