Progress in research and technological developments of phase change materials integrated photovoltaic thermal systems : The allied problems and their mitigation strategies

The efficiency of solar cells and photovoltaic (PV) panels are lacking significantly due to its surface overheating by the incident solar radiation. Indeed, the generated heat energy is harnessed by integrating a thermal system into PV panel, which introduces a photovoltaic thermal (PVT) system. Phase change materials (PCM)s are a class of energy material that is intended to facilitate thermal regulations of photovoltaic (PV) panel. Despite, PVT systems are allied with numerous problems like, integration technique, increase in overall weight of the system, dust accumulation, complication of tracking etc., which are of utmost importance to be resolved. The foremost aim of the review is to analyze the current technologies and allied problems of PVT system, the impact of the overall weight of the system on the PVT systems, detailed assessment of recent advancements in soil mitigation techniques, and the economic benefit of the PVT systems. Also, this review article is specifically intended to discuss on a) concerns allied with PV and PVT system integrated with PCM for thermal regulation; b) framework intimidating the performance of PCM-integrated PVT system; and c) mitigation techniques to resolve the problems and enhanced the performance of PCM integrated PVT system. A elaborative technical exploration on common issues associated with both PV and PVT systems in terms of surface cleaning towards dust mitigation via advanced mechanisms and futuristic technologies is comprehensively presented. A new possible sustainable solution towards enhancing the performance of PV and PVT systems is also provided. A summary of numerous research works conducted on enhancing the performance of PVT system integrated with PCM at different global locations is summarized. Furthermore, this review also discusses the economic analysis of PVT system integrated with PCM along with a summary of technical challenges and future outlook of PCM integrated PVT system to boost sustainable development

Absorber Tube with Internal Pin-Fins for Solar Parabolic Trough Collector

Solar parabolic trough collectors exploit solar energy for power generation in solar thermal power stations. These systems require long arrays of reflective troughs with absorber tube running along the axis of parabolic dish. A successful attempt to reduce the length of arrays was accomplished by experimentally analysing the modifications done in absorber tube. Two out of three tubes were fabricated and they were employed to obtain the performance parameters through experimentation conducted at VIT University, Vellore, India. Distilled water was used as the working fluid. Maximum efficiency of 39.12% was obtained at 451.6 W/m2 of direct normal irradiance (DNI) for absorber tube with internal pin-fins and without glass tube (AFWGt) compared to 8.15% obtained at same value of DNI and other conditions for simple absorber tube without glass cover (AWGt). Cylindrical parabolic trough available at the university was utilized, providing the basis for designing and fabrication of the tubes. Plots for varying mass flow rate at interval of 10 minutes were made against instantaneous thermal efficiency and heat utilized, for direct normal irradiance vs. temperature difference across the tubes and instantaneous thermal efficiency. Through the experimentation conducted, better performance was procured compared to earlier works. Thus, the proposal infers that absorber tube with internal fins has good scope for its application, both domestically as well as industrially. It also calls for further research and development of proposed techniques so as to achieve better performance curves

Recent developments in chemistry, coordination, structure and biological aspects of 1-(acyl/aroyl)-3-(substituted) thioureas

1-(Acyl/aroyl)-3-(substituted)thioureas are privileged architectures that have received remarkable attention of researchers in view of their variable topological aspects, binding modes and broad spectrum promising pharmacological properties. Reactivity of acyl thiourea derivatives has presented various organic transformations into other demanding scaffolds and this is an attractive strategy for synthetic chemists to access heterocyclic cores. Multiple binding sites make them flexible ligands for complexation with transition metals thus occupying a distinct position in coordination chemistry. 1-(Acyl/aroyl)-3-(substituted)thioureas have also emerged as attractive candidates in various fields such as ion sensors, corrosion inhibitors, molecular electronics, in metal extraction and in pharmaceuticals. The medicinal chemistry of this organo-sulfur framework and the derived metal complexes has witnessed fantastic progress in the current era. In continuation of our efforts to compile data on the structural aspects and numerous applications of 1-(acyl/aroyl)-3-(substituted)thiourea analogs, continuous advances have prompted us to present an overview of the last 2 years literature on this exciting family of compounds through this review article.Fil: Saeed, Aamer. Quaid-i-Azam University; PakistánFil: Qamar, Rabia. Quaid-i-Azam University; PakistánFil: Fattah, Tanzeela Abdul. Quaid-i-Azam University; PakistánFil: Flörke, Ulrich. Universität Paderborn; AlemaniaFil: Erben, Mauricio Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentin