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At present municipal solid waste (MSW) has become one of the biggest national concerns because mismanagement of MSW deteriorates the purity and cleanliness of the environment. In this direction, this manuscript discusses the details of generation, characterization of MSW, and current practice of municipal solid waste management in Himachal Pradesh (HP), a state in the northern region of India. Himachal Pradesh generates approximately 342.35 tons per day (TPD). Thus, it is a massive challenge for the municipalities of HP to manage it in a hilly region. Hilly regions of HP are prone to rapid climate change i.e., rainfall and snowfall in winter and hence found to be one of the important factors that affect the collection and treatment process of waste management. Indeed, the generation of waste decisively depends upon the tourism business. Further, the tourism business also depends upon seasonal variation. Difficult terrain and socio-economic condition of local people make waste disposal and transportation more difficult for the appropriate planning of the management of municipal solid waste. The characterization studies show that the biodegradable fraction in MSW is more than 50% which indicates a significant energy potential. The manuscript covers issues and challenges in waste management due to climatic conditions in the hilly regions of HP and also recommends the best suitable remedial measures for the proper management of the existing MSW system and its appropriate treatment alternatives. Hence this manuscript provides a wholesome glimpse of the possibilities of energy, global warming potential, and the economic aspects of MSW in the regions of HP. The findings will help the stakeholders and policymakers in better decision-making.

Aim of the present work is to see the performance of recycled demolished construction material by analysing its compressive strength for non-load bearing components of structure like boundary wall and non-load bearing walls. Crushed pieces of demolished construction material having size 10 mm–60 mm were used as an option over coarse aggregate. The crushed demolished construction material was used as 10% to100% of weight with coarse aggregate for systematic preliminary investigation. Performance of the recycled coarse aggregate in concrete mix was analysed by comparing the 28 days compressive strength of the different concrete mix samples prepared with Indian Standard (IS) recommended design mix. It was observed that the maximum compressive strength was found at 60 percent usage of the demolished concrete waste and strength results were comparable to the control mix up to 80 percent usage of the demolished concrete waste aggregate.

The age of modernization comes with its own set of flaws, which has to be mitigated as sooner as possible for a sustainable future. It is a well-established fact that the need for energy in this age of technology is at stake due to the incessant use of carbon based fossil fuels. Fossil fuels in themselves are not enough. They are very much likely to be exhausted sooner than expected. Therefore, a new clean and renewable alternative has to be adopted which could be able to meet the energy demand. Hydrogen Energy may be one of the most viable and suitable alternative ways to mitigate the energy demand, without affecting the environment. The project work is focused on the optimization of the key operating parameters of the electrolyser coupled with a solar photovoltaic (PV) system for hydrogen production using the Taguchi technique. In this work ten operating parameters have been selected using an L27 (310) orthogonal array for optimization. Based on the 27 orthogonal arrays, it was found that the maximum hydrogen production is 319.35 Ncm3/hr. After applying the Taguchi technique, found that the maximum hydrogen production was 645.89 Ncm3/hr., which gives 50.56% increment as compared to the highest value of production obtained from orthogonal array.

In the present scenario, space heating/cooling has become essential for human comfort. Most of the demand is fulfilled by conventional devices, which consume high-grade energy and emit toxic gases. Due to this, now focus is turned on how to harness the renewable source of energy is becoming important. In recent times, GSHP systems are very popular for space conditioning applications. The ground heat exchanger (GHX) extracts and rejects the heat from the ground for heating & cooling, respectively. This work is proposed for optimizing the total length of GHX to achieve higher performance of GSHP system by Taguchi optimization technique. Five influencing operating parameters for GHX have been considered using the L27(53) orthogonal array. Lower the better concept is used for GHX length optimization. The results are investigated through optimum values of ANOVA and S/N ratio analysis. Simulation using L27 orthogonal array were carried out by considering 1.5 ton of total heating demand in wintertime. Based on trial runs, it is found that the minimum and maximum lengths were 12.17 m and 137.55 m, respectively. The optimum length of GHX is 11.05 m, which is 9.17% lower than the value predicted by the L27 orthogonal arrays.

The aim of this study is to find the best working fluid for Organic Rankine Cycles (ORCs) at specific temperature limits, with a focus on thermodynamic analysis, environmental impact, and protection. A subcritical Rankine cycle with organic working fluids was used to produce electricity using a low-temperature heat source. The six organic fluids (R600, R245fa, R290, R134a, R123 & R600a) were selected, studied, and compared for ORC applications to get high efficiency and COP. The study found that because of pressure factor, efficiency, expander, R600a, R134a & R290 are the most preferable choices. In terms of COP and pressure ratio, R600a is best among the six fluids. However, if we consider factors like mass flow rate, refrigerating capacity and COP, then R245fa & R123 are the suitable choices. However, the ODP of R123 is found to be 0.012, and given the targeted zero tolerance for ODP compounds, R123 working fluid would be phased out sooner than expected, especially given its significant GWP of 76. The GWP of R245fa is at an intolerable level of 820.

The aim of the present work is to process densified Al2O3/ZrO2/CeO2 composites, their microstructural characterization and study of their mechanical properties. Alumina ceramic material and alumina based composites are sintered at 1650°C via conventional sintering. Further 3 weight percent of Ni or TiO2 are added in Al2O3/ZrO2/CeO2 compositions and effect on densification and mechanical properties is also studied. Al2O3-40ZrO2-3Ni composite achieved the highest density of 97%. Presence of major phases Al2O3, t-ZrO2, CeO2 peaks are seen in XRD pattern with other intermetallic phases peaks on addition of Ni or TiO2.SEM images revealed the distribution and bonding between grains. EDS confirmed the presence of Al, Zr, Ce, Ni, Ti and O elements in sintered composites. Hardness varied from 9 GPa to 14.35 GPa and the fracture toughness varied from 2.3 to 4.9 MPa.m1/2 with the variation in cermet composition. Al2O3-40ZrO2 composite has the highest hardness of 14.35 GPa and Al2O3-40ZrO2-3Ni composites has the highest fracture toughness of 4.9 MPam1/2. Alumina is not densely sintered which resulted in reduced mechanical properties. Transformation of m-zirconia to t-zirconia crystal structure at high sintering temperature is observed and t-zirconia crystal structure retained on cooling which resulted in toughening of alumina composite. Presence of round pores and pulled out ceria particles visible in ceria added composites which resulted in reduced mechanical properties.

Purpose Development, characterization and solubility study of solid dispersion of Quercetin with Plasdone K-90, Plasdone K-30 and Eudragit RS-100 by solvent evaporation technique. Methods: The prepared SDs were evaluated for percentage yield, drug content, solubility, dissolution and other physicochemical properties. The SDs were prepared by conventional SDs technique shows improvement in solubility, dissolution and other physicochemical properties comparative to pure Quercetin. The prepared SDs were characterized using powder XRD, DSC, SEM and FTIR techniques. The prepared SDs exhibit enhanced release profiles of pharmaceutical agent due to the increased wetting properties and surface of drug available for dissolution. A comparative evaluation of the dissolution of quercetin SDs and pure drug (quercetin) was carried out. Results: Dissolution of Quercetin improved significantly in SDs as compared to pure drug. IR spectroscopy and DSC showed no change in crystal structure of Quercetin. Conclusion: In conclusion, the results of this work suggest that solvent evaporation technique is a useful technique to enhance the solubility and dissolution rate of poorly water-soluble.

In the present investigation prealloyed Fe-Cr-Mo and Fe-Mo alloy steel with 0.6 wt.% graphiteaddition are processedvia conventional sintering technique followed by their study of physical and mechanical properties. Powder mixtures are compacted at 600 MPa pressure and sintered in an atmosphere of N 2 -H 2 at 1200°C held for one hour with 6.0°C/minute cooling rate. Relative density (>90%)is achieved for both the alloys. XRD pattern revealed the major peaks of ferrite and iron carbide phases. SEM micrographs of as sintered Fe-Cr-Mo-0.6C and Fe-Mo-0.6C alloy reveal the presence of ferrite, pearlite and bainite structurewith some carbide at the boundaries.SEM micrographs of as sintered oil quenched Fe-Cr-Mo-0.6C and Fe-Mo-0.6C alloy reveal the presence of martensite structure. EDS confirmed Cr, Mo, Fe and carbon elements in sintered samples with respect to their compositions. As sintered Fe-Mo-0.6C alloy hardness is higher than Fe-Cr-Mo-0.6C alloy, reason attributes to it is the presence of dominant bainitic structure in as sintered Fe-Mo-0.6C alloy resulted in high hardness value (195HV5) in comparison of Fe-Cr-Mo-0.6C alloy. Whereas sintered Fe-Cr-Mo-0.6C alloy resulted in high hardness value than Fe-Mo-0.6C alloy on quenching in water and oil medium, reason being presence of Cr more resist the diffusion of carbon in iron in faster cooling medium resulting in high hardness of sample in water and oil.

In the present work, the unlubricated sliding wear behavior of conventionally sintered TiCN-WC-Ni/Co cermets with or without TaC is studied against steel and cemented carbide (WC-Co) ball at 5, 10 or 20 N load. With change in the cermet composition, sliding load and counter bodies coefficient of friction (COF) varied from 0.25 to 1.17. Wear rate of the cermet increased when slid against cemented carbide. In general, worn surfaces of TiCN based cermets reveal the adhesion, grain pull-out and layer formation at low load and grain pull-out, surface polishing and layer formation at high load. Reduced wear is observed for TaC added TiCN-WC-Ni/Co cermet.

Fe-Cr-Mo alloy steel with addition of 0.4 weight percentage graphite has been processed via Powder Metallurgy route. Green compacts prepared at 650 MPa pressure were sintered at 1120°C and 1200°C for one hour and cooled at 6.0°C/min in a stream of nitrogen and hydrogen (90%N 2 +10%H 2 ). The sintered microstructure consists of a ferrite and pearlite with some cementite at the boundaries. Presence of chromium oxide was observed in samples sintered at 1120°C. In the present sintering conditions there was no significant difference in the density achieved at 1120°C and 1200°C. No oxide formation was observed at 1200°C. This resulted in improved mechanical properties as compared to specimen sintered at 1120°C.