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A series of zinc substituted cobalt ferrite samples i.e., Co1-xZnxFe2O4 (x = 0.0–0.6) were synthesized by sol-gel method. X-ray diffraction patterns confirmed the formation of pure-phase cubic spinel structure in the prepared samples. Cation distribution between the tetrahedral and octahedral sites were estimated by refining the XRD patterns by Rietveld method. Magnetic studies revealed that the saturation magnetization is maximum for x = 0.4 sample; whereas the values of coercivity, magnetic anisotropy constant and magnetostriction decreased with increasing x. However, a considerable enhancement in the magnitude of strain sensitivity is obtained for x = 0.4 sample in comparison to other substituted samples. The observed variations in the magnetic results are discussed on the basis of site occupancies of the cations and decreased anisotropy of the prepared samples whereas the microstructure plays insignificant role. Moreover, the dielectric measurements indicated a reasonable value of dielectric constant at low frequencies along with a low value of ac conductivity for x = 0.4 sample due to electron–hole compensation at octahedral sites of the spinel structure. Here, it is suggested that x = 0.4 composition exhibits the optimal magnetic and dielectric properties in the Co1-xZnxFe2O4 system that could make this composition as a potential candidate for stress sensor applications.

Polytetrafluoroethylene (PTFE) was coated on 316L stainless steel (SS) substrate through a spin coating technique to enhance its corrosion resistance properties in hydrochloric acid (HCl) and nitric acid (HNO3) medium. Scanning electron microscopy (SEM) revealed the morphology of the coated and uncoated substrates and showed a uniform and crack-free PTFE coating on 316L SS substrate, while a damaged surface with thick corrosive layers was observed after the electrochemical test on the uncoated sample. However, an increased concentration of HCl and HNO3 slightly affected the surface morphology by covering the corrosive pits. An atomic force microscope (AFM) showed that the average surface roughness on 316L SS and PTFE coating was 26.3 nm and 24.1 nm, respectively. Energy dispersive X-ray spectroscopy (EDS) was used for the compositional analysis, which confirmed the presence of PTFE coating. The micro Vickers hardness test was used to estimate the hardness of 316L SS and PTFE-coated substrate, while the scratch test was used to study the adhesion properties of PTFE coating on 316L SS. The anticorrosion measurements of 316L SS and PTFE-coated substrates were made in various HCl and HNO3 solutions by using the electrochemical corrosion test. A comparison of the corrosion performance of PTFE-coated substrate with that of bare 316L SS substrate in HCl medium showed a protection efficiency (PE) of 96.7%, and in the case of HNO3 medium, the PE was 99.02%, by slightly shifting the corrosion potential of the coated sample towards the anodic direction.

The purpose of this research is to study in detail about the site selection process in nuclear power plant (NPP) construction. There are various factors that contribute to the site selection which involves in-depth investigation and detailed evaluation before the site is being finalized and proposed. There are two main objectives in siting of NPP; ensuring the technical and economic feasibility of the plant and minimising potential adverse impacts on the community and environment. Geographical environment also plays an important role in siting of NPP where the source of water should be abundance. Country requirement for siting of NPP would be different for every country where they are controlled by their own regulatory bodies. About 64 published studies (1967-2017) are reviewed in this paper. It is marked from the literature survey articles that siting process is extremely crucial step in constructing NPP where public acceptance is one of the main factors, that need to be considered. Malaysia is one of the new countries embark in nuclear industry that still is in the planning phase to plan and construct its first NPP.

This Paper discussed the historical review, current status of ocean current turbine, challenges and problems in the way of the ocean current turbine commercialization. As we known that fossil fuel resources in the world are limited and we can't depend on them for the future energy needs of the world. For this purpose the researcher have find such sources of energy which are sustainable, green, environment friendly and have no impact on human lives, which includes renewable energy sources like solar, wind, and ocean energy sources. In this review paper, we also focused on the initiative of the ocean current energy technology and the efforts of different countries, companies and scientist for the development of ocean current turbine to extract power from ocean current energy including Marin Current Turbine Ltd (MCT), Florida Atlantic University (FAU). We summarized the current status and recent development in the field of ocean current turbine. We discussed some earlier projects and prototypes. The paper also discusses the impact of the ocean current turbine on the environment and marine life. Some of the current limitation and problems are also identified in the way of ocean current turbine development like grid connection.

The objective of this study endeavor is to describe the design of an environment friendly captive micro hydel power plant at the sewerage treatment plant outlet fall at Lai Nallah located in I-9 Islamabad. It will use sewerage water of CDA as discharge water to run the turbine of the micro hydel power plant to generate electricity. The important phases of the project are to carry out survey for collection of data about hydrology, quantity of flow of water, fall head, geology and design of an efficient turbine. Complete design calculations of turbine have been performed along with static and model analysis of the turbine. Key parameters to increase efficiency of cross-flow turbine are discussed.

Energy use for domestic purposes can be considered as the prime consumer ofPakistan’s energy resources. Residential buildings are one of the consumers of energyfor space cooling. In this paper we studied the energy consumption for space coolingof a residential building for located in Islamabad. The relevant data of construction,operation schedules, occupancy and lighting of the selected residential building wascollected and analyzed through simulation using eQuest energy simulation tool. Themodel was considered as the baseline model for further analysis. Energy efficiencymeasures were applied to windows area, windows glazing type, Area lighting, heatingventilating and air conditioning (HVAC) system thermostat set point and EnergyEfficiency ratio of the HVAC system. Results showed 38.5 % decrease in the energyconsumption as compared to the baseline model.

The office buildings are main consumers of energy for space cooling in Pakistan. In this study a three storied office building was selected for studying the energy consumption. The data was collected from the se- lected building and was entered to eQuest software proram for simulation. This model was termed as baseline model. The building was further optimized with the windows area and glazing type separately. The results were compared with the baseline model. Simulation results showed that 10.5% of electrical energy used for cooling purposes can be saved by reducing the windows area. And up to 5% of the energy can be saved by using the double glazed brown tinted windows instead of single glazed windows.

Four Bedroom detached house was selected for analysis of energy performance of residential buildings in Islamabad. The actual building was studied for the energy consumption by simulating in eQuest, the whole building energy simulation program. This served as Baseline model for the analysis. This building uses electrical energy for space cooling. Energy efficiency measures were applied to the building by optimizing the windows area and changing the glazing type. Results show that employing the selected windows area reduction measure can save up to 7.2 % electrical energy as compared to the baseline model while applying the double window glazing for the baseline window size pay back 5.9% electrical energy saving of the energy used for space cooling in comparison to the baseline model. Index Terms— Simulation, Building, energy, electrical energy, efficiency, Baseline, Energy efficient model

Vibration characteristics of an ocean current turbine blade have been analyzed using Design foil, BET tool, Pro/Engineer and Finite Element Package ANSYS. Natural frequencies and mode shapes of a turbine blade can be evaluated by Vibration Analysis. It can also serve as a starting base for another, dynamic analysis, such as a transient dynamic analysis, or a spectrum analysis. The natural frequencies and mode shapes are important parameter in the design and analysis of an ocean current turbine blade. Modal analysis can also be performed on a pre-stressed spinning turbine blade. It has been investigated that the blade would not fail in an ocean current of 2.3 to 2.5 m/s that can produce power production up to 151 KW. The blade is of Composite structure with carbon fibers and foam core. It is also facilitated with two webs of carbon fibers to add shear rigidity. Eight design cases of blade were analyzed involving the differences in geometry, material properties and internal structures. Results from the vibration analysis revealed that the recommended blade design have adequate frequency difference than the frequency of other components of turbine like rotor, assembly to produce proposed power of 151 KW without any resonance or structural failure. Deflection analysis and Principal stress analysis have been conducted that showed the proposed blade design have adequate strength.

A new diagnostic scheme is presented for ball bearing localized faults based on pattern recognition (PR) methods, which utilize preprocessed time domain features. The features are statistically processed (FP) using their central tendency (CT) estimations, prior to the classification process. Vibration data is acquired from faulty bearings, and the features are extracted to form data set. The FP algorithm deals with outliers present in the features by suppressing them. Utilization of the smoother feature distributions reduces the unwanted impact of vibration randomness and background noise in PR based fault diagnostic procedure. This significantly enhances the classification accuracy of classifiers. The results are compared with similar work in terms of maintaining an optimum classification accuracy of a diagnostic system with minimum number of features. The proposed scheme provides 93.6% classification accuracy for four bearing faults employing three features only, and even higher using additional features.

Due to combination of factors, such as environmental concerns, high oil prices and the potential for peak oil, development of cleaner alternative fuels and advanced power systems for vehicles has become a high priority for many governments and vehicle manufacturers around the world. Use of Gasoline as an alternative fuel in Gasoline engine is becoming a need, looking at the scarcity of petroleum fuels in near future. This paper investigates the influence of compression ratio and ethanol-gasoline blending to find the effects on four-stroke SI engine performance. In this research, air cooled engine having compression ratio of 9.1 & 9.7 is used. Fuel blend E50 is used in the study and engine operated at a speed range of 600-1100 rpm. Maximum power was obtained for E50 fuel at a compression ratio of 9.1, while, a minimum fuel consumption rate was obtained at a compression ratio of 9.7. This clearly depicts that as compression ratio increases, fuel consumption rate decreases considerably. Further, experimental results showed that comparing several blends, 50% ethanol is cost and power effective for the four-stroke SI engine.