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1.
In this paper, an experimental study of the conventional solar still (CSS), the conventional solar still with glass cooling (CSSGC), the conventional solar still with basin heating (CSSBH), and the conventional solar still with glass cooling and basin heating (CSSGCBH) was carried out on the basis of the distilled water production, the energy efficiency (EnE), the exergy efficiency (ExE), and economic analysis. The CSSGC and CSSBH contain Peltier modules for cooling the glass and heating the basin. The evaporative heat transfer coefficient for all the experimental stills was calculated. The values of daily distilled water production from the CSSGCBH, CSSBH, CSSGC, and CSS were 4.56, 3.79, 2.49, and 1.89 kg/m2, respectively. The daily distilled yield of the CSSBH and CSSGCBH were increased by 58.55% and 50.13%, respectively, as compared with the CSS. Moreover, the daily EnE and ExE of the CSSGCBH were 27.03% and 3.5%, respectively, whereas the EnE and ExE of the CSS were 10.88% and 1.3%, respectively. Furthermore, the cost of distilled water production was found to be 0.26, 0.35, 0.53, and 0.64 $/day for the CSS, CSSGC, CSSBH, and CSSGCBH, respectively, if the selling price of the distilled water was Rs10.  相似文献   
2.
The International Journal of Advanced Manufacturing Technology - This study attempts to incorporate SiC particles in the weld zone during friction stir welding of Al 6351 alloy. SiC particles of...  相似文献   
3.
The objective of this investigation was to find the effect of ethanol–gasoline blends as fuel on the performance and exhaust emission of a spark ignition (SI) engine. A four-stroke three-cylinder SI engine was used for this study. Performance tests were conducted for the three blends E5 (5% ethanol), E10 (10% ethanol) and E15 (15% of ethanol) as well as E0(100% gasoline) to evaluate their brake thermal efficiency, specific fuel consumption and mechanical efficiency, while exhaust emissions were also analysed for carbon monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2) and oxides of nitrogen (NOx) with varying torque conditions and constant speed of the engine. The results showed that blends of gasoline and ethanol increased the brake power, brake thermal efficiency and the fuel consumption. The CO and HC emissions concentration in the engine exhaust decreased while the NOx concentration increased.  相似文献   
4.
The ever-growing demand for energy storage devices necessitates the development of novel energy storage materials with high performance. In this work, copper molybdenum sulfide (Cu2MoS4) nanostructures were prepared via a one-pot hydrothermal method and examined as an advanced electrode material for supercapacitor. Physico-chemical characterizations such as X-ray diffraction, laser Raman, field emission scanning electron microscope with elemental mapping, and X-ray photoelectron spectroscopy analyses revealed the formation of I-phase Cu2MoS4. Electrochemical analysis using cyclic voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy (EIS) showed the pseudocapacitive nature of charge-storage via ion intercalation/de-intercalation occurring in the Cu2MoS4 electrode. The Cu2MoS4 electrode delivered a specific capacitance of 127 F g?1 obtained from the CD measured using a constant current density of 1.5 mA cm?2. Further, Cu2MoS4 symmetric supercapacitor (SSC) device delivered a specific capacitance of 28.25 F g?1 at a current density of 0.25 mA cm?2 with excellent rate capability. The device acquired high energy and power density of 3.92 Wh kg?1 and 1250 W kg?1, respectively. The Nyquist and Bode analysis further confirmed the pseudocapacitive nature of Cu2MoS4 electrodes. The experimental results indicate the potential application of Cu2MoS4 nanostructures as a novel electrode material for energy storage devices.  相似文献   
5.
This work aims at augmenting the amount of potable water using MgO and TiO2 in stepped solar still. Experiments were carried out for the climatic conditions of Chennai, India, with two different concentrations of nanofluids inside a stepped basin under three different cases. Results show that there is an improvement in yield of fresh water from stepped solar still by 33.18% and 41.05% using 0.1% and 0.2% volume concentration of TiO2 nanofluid, respectively, whereas the freshwater yield from stepped still with MgO nanofluids improved by 51.7% and 61.89%. Furthermore, the economic analysis revealed that the cost of potable water from the modified solar still reduced from 0.029 to 0.016 $/kg. Similarly, the useful annual energy, yearly cost per kilogram, and annual cost per kilowatt hour are significantly profitable with the use of MgO nanofluid in the stepped basin and found as 512.46 kWh, 0.025 $/kg, and 0.026 $/kWh, respectively. It is also found that the cost of potable water from the modified still significantly increases as the amount of fresh water produced is decreased with increased fabrication cost of the solar still.  相似文献   
6.
This paper presents the computational analysis of convective heat transfer characteristics, pressure drop, and entropy generation characteristics of Al2O3/water nanofluids in a noncircular duct (triangular) using a single phase approach under a turbulent flow regime. The thermal and pressure drop characteristics of different concentrations of Al2O3 nanoparticles (NPs) and the analysis were carried out in Fluent software using a k‐ε approach under constant wall heat flux around the boundary. The results show that there is an increase in pressure drop and thereby an increase in friction by 20% for the smooth condition. The total pressure drop between the entry and exit section of the duct is increased to approximately 84.2% and 85.6% for a higher Reynolds number (Re = 10 000) compared with that of base fluid. Similarly, the entropy generation of water is increased by 40% as compared with 0.05% and 0.1% Al2O3 NPs. There is also a decrease in entropy generation identified while there is an increase in the Reynolds number. The convective heat transfer of 0.05% and 0.1% nanofluid has a similar trend with increased Reynolds number. The maximum performance is observed at the Reynolds number (Re = 4000) and found to be 1.29 for 0.1% concentration, whereas, the fluid at 0.05% is observed to be at 1.23. At a higher Reynolds number (Re = 10 000) the performance index decreased to approximately 1.19 and 1.25 for 0.05% and 0.1%, respectively.  相似文献   
7.
In this work, the sugarcane bagasse fiber was used as a filler to make a new type of biodegradable composite, using the cardanol resin, as a fully biodegradable thermosetting polymer matrix. Biocomposite performance was improved by chemically modified bagasse fiber using alkaline treatment. Two sets of composites were prepared with a fiber length of 10 and 20 mm with various weight percentages viz., 0, 5, 10, 15, and 20 of cardanol resin using a compression molding machine. The mechanical properties were studied using some tests and the morphological study in flexural fractured specimens was carried out using SEM. The thermal properties of biodegradable polymer composites were evaluated using TGA. The chemical formation of the new biocomposites was also examined by the FT-IR spectroscopy technique. The result proved that the morphology of the composites has improved the bonding between the fiber and resin, thus leading to enhancement of the mechanical properties. The result had shown the tensile and flexural strength with an increase in the range of bagasse fiber up to 15 wt% in both the sets. The TGA results showed that biocomposites of 15 wt% in both sets had the highest thermal stability. This investigation recommended the possibility of introducing bio-fiber obtained from waste agricultural residues in polymer matrix composites.  相似文献   
8.
Wireless Personal Communications - Wireless Sensor Network plays a vital role and part of real time communication applications. Location of unknown node is difficult to find in the presence of...  相似文献   
9.
An efficient analytical method was developed and validated using a modified QuEChERS method and LC-MS/MS for the detection and quantification of neonicotinoid insecticide residues in rice whole grain and rice straw. The samples were extracted using acetonitrile and cleaned up by dispersive solid-phase extraction. Validation based on five fortification levels showed good recoveries of neonicotinoids ranging from 75% to 116 % and 60% to 105 % for rice whole grain and straw, respectively. The precision ranged between 3% and 17 %, and 2% and 10 % for grain and straw, respectively. The limit of detection was from 0.007 to 0.0084 mg kg?1 and 0.005 to 0.15 mg kg?1 and the limit of quantification was in the range of 0.024–0.028 mg kg?1 and 0.016–0.051 mg kg?1 for rice whole grain and rice straw, respectively. Monitoring of farm gate samples indicated that, out of 24 samples, 1 rice whole grain sample was contaminated with thiamethoxam residues (0.07 mg kg?1).  相似文献   
10.
It has been previously reported that the addition of boron to Ti–6Al–4V results in significant refinement of the as-cast microstructure and enhancement in the strain hardening. However, the mechanism for the latter effect has not been adequately studied. The aim of this study was to understand the reasons for the enhancement in room temperature strain hardening on addition of boron to as cast Ti–6Al–4V alloy. A study was conducted on slip transmission using SEM, TEM, optical profilometry and four point probe resistivity measurements on un-deformed and deformed samples of Ti–6Al–4V–xB with five levels of boron. Optical profilometry was used to quantify the magnitude of offsets on slip traces which in turn provided information about the extent of planar or multiple slip. Studies on deformed samples reveal that while lath boundaries appear to easily permit dislocation slip transmission, colony boundaries are potent barriers to slip. From TEM studies it was also observed that while alloys containing lower boron underwent planar slip, deformation was more homogeneous in higher boron alloys due to multiple slip resulting from large number of colony boundaries. Multiple slip is also proposed to be the prime cause of the enhanced strain hardening.  相似文献   
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