Dysprosium doped copper oxide (Cu1-xDyxO) nanoparticles enabled bifunctional electrode for overall water splitting

The production of hydrogen, a favourable alternative to an unsustainable fossil fuel remains as a significant hurdle with the pertaining challenge in the design of proficient, highly productive and sustainable electrocatalyst for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). Herein, the dysprosium (Dy) doped copper oxide (Cu_1-xDy_xO) nanoparticles were synthesized via solution combustion technique and utilized as a non-noble metal based bi-functional electrocatalyst for overall water splitting. Due to the improved surface to volume ratio and conductivity, the optimized Cu_1-xDy_xO (x = 0.01, 0.02) electrocatalysts exhibited impressive HER and OER performance respectively in 1 M KOH delivering a current density of 10 mAcm^?2 at a potential of ?0.18 V vs RHE for HER and 1.53 V vs RHE for OER. Moreover, the Dy doped CuO electrocatalyst used as a bi-functional catalyst for overall water splitting achieved a potential of 1.56 V at a current density 10 mAcm^?2 and relatively high current density of 66 mAcm^?2 at a peak potential of 2 V. A long term stability of 24 h was achieved for a cell voltage of 2.2 V at a constant current density of 30 mAcm^?2 with only 10% of the initial current loss. This showcases the accumulative opportunity of dysprosium as a dopant in CuO nanoparticles for fabricating a highly effective and low-cost bi-functional electrocatalyst for overall water splitting.     

Acoustic emission technique for leak detection in an end shield of a pressurised heavy water reactor

This paper discusses the successful application of the Acoustic Emission Technique (AET) for detection and location of leak paths present on the inaccessible side of an end shield of a Pressurised Heavy Water Reactor (PHWR). The methodology was based on the fact that air and water leak AE signals have different characteristic features. Baseline data was generated from a sound end-shield of a PHWR for characterizing the background noise. A mock up end-shield system with saw cut leak paths was used to verify the validity of the methodology. It was found that air leak signals under pressurisation (as low as 3 psi) could be detected by frequency domain analysis. Signals due to air leaks from various locations of a defective end-shield were acquired and analysed. It was possible to detect and locate leak paths. Presence of detected leak paths were further confirmed by alternate test.     

Role of Silicon Coupling Grafted Natural Fillers on Visco-Elastic,Tensile-Fatigue and Water Absorption Behavior of Epoxy Resin Composite

Silicon - This work investigates the influence of silicon based coupling agents on visco-elastic properties of natural filler dispersed epoxy resin composites. Also this work attempts to explore...     

Structural integrity assessment of the containment structure of a pressurised heavy water nuclear reactor using impact echo technique

The impact echo technique is based on the use of transient stress waves for non-destructive detection of flaws in concrete structures. Impact-echo testing has been carried out for assessment of the structural integrity of the ring beam of a pressurised heavy water nuclear reactor. In order to develop the test procedure for carrying out impact echo testing, mock up calibration blocks were made. The detectability of the impact echo system has also been established in terms of the depth and the lateral dimension of the detectable flaw for the ring beam under consideration. Based on the optimised test parameters identified with the help of the studies carried out on the mock up blocks, impact echo testing was carried out on the ring beam of the reactor containment structure, for assessing its structural integrity.     

Hydriding characteristics of palladium and platinum alloyed FeTi

Effect of alloying on the hydriding characteristics of FeTi with noble metals such as platinum and palladium (5% by weight) has been investigated. It is observed that palladium has a favourable effect with respect to easy activation, decreased hysteresis and lower plateau pressures for hydrogen absorption and desorption process. For Pd/FeTi, a saturation composition of Pd/FeTiH_1.85 having the -phase, has been obtained. Unlike this, for Pt/FeTi, the total hydrogen absorption is decreased significantly and a saturation composition of Pt/FeTiH_1.5 having only ₂ phase, is observed.     

AH-64D main transmission accessory drive spur gear installation fault detections

The US Army has launched an aggressive program to implement condition based maintenance on its rotary wing assets. Condition Based Maintenance takes advantage of technology developments in the areas of machinery monitoring, signal processing and fault modeling to reduce the cost of ownership through improved maintenance procedures. Documenting the reduction in maintenance burden, cost savings and increased safety through early detection of helicopter faults is an important step in justifying the program. This paper describes a novel technique used to detect a serious fault in the accessory section of the AH-64D Apache main transmission. The technique determines if the primary or secondary clutch system is driving the aircraft accessories through a tachometer speed ratio. The method has identified three aircraft operating on the secondary system allowing Army maintenance crews to replace the affected transmissions and quickly restore the aircraft to operational status.     

Magnetization study of Fe-doped ZnO co-doped with Cu: Synthesized by wet chemical method

Fe- and Cu-doped ZnO of nominal compositions Zn_0.95Fe_0.05O and Zn_0.94Fe_0.05Cu_0.01O were synthesized by a wet chemical route. X-ray diffraction analysis of the samples annealed at 575 K showed that they are single phase without any secondary phases. DC magnetization measurements of Cu co-doped samples (Zn_0.94Fe_0.05Cu_0.01O) as a function of field at room temperature showed ferromagnetic signature while the samples without Cu co-doping (Zn_0.95Fe_0.05O) are paramagnetic in nature. On increasing the temperature of annealing from 575 K to 1,075 K an impurity phase emerges in both the samples, which has been identified as a variant of ZnFe₂O₄. Both the samples heated at and above 1,075 K are found to be paramagnetic at room temperature. These observations, the absence of room temperature ferromagnetism in Zn_0.95Fe_0.05O and the disappearance of ferromagnetism in Zn_0.94Fe_0.05Cu_0.01O on raising the temperature of annealing clearly rules out the likelihood of room temperature ferromagnetism arising from the impurity phases like γ-Fe₂O₃ and/or ZnFe₂O₄ that might have been formed during the synthesis. Our results strongly suggest that room temperature ferromagnetism in Zn_0.94Fe_0.05Cu_0.01O can be attributed to the formation of a secondary phase of Cu-doped ZnFe₂O₄.     

Antifungal activity of five different essential oils in vapour phase for the control of Colletotrichum gloeosporioides and Lasiodiplodia theobromae in vitro and on mango

Mango fruit has high commercial value; however, major postharvest losses are encountered throughout the supply chain due to postharvest diseases. These results lead to the search for natural fungicide for postharvest diseases control. The antifungal effects of five essential oils (thyme, clove, cinnamon, anise and vitex) were assessed by disc volatilisation method. Thyme oil vapours at 5 μL per Petriplate, and clove and cinnamon oil at 8 μL per Petriplate showed 100% growth inhibition of mango pathogens in vitro. GC/MS analysis of essential oil showed thymol (23.88), o‐cymol (23.88) and terpinolene (23.88) as the major constituents of thyme oil. Clove and cinnamon oils contain 3‐allyl‐2‐methoxyphenol (37.42%) and benzofuran 3‐methyl (17.97%), respectively. Thyme oil as a fumigant at 66.7 μL L^?1 showed a significant (P < 0.05) inhibition on postharvest pathogens of mango fruits stored at 25 °C for 6 days. Results of our study suggest the possibility of using thyme oil as an alternate natural fungicide to manage postharvest diseases in mango.     

A support vector regression approach to detection in large-MIMO systems

We propose a support vector regression approach for symbol detection in large-MIMO systems employing spatial multiplexing. We explore the applicability of machine learning algorithms, in particular support vector machines, to address one of the recent research problem in communications.The machine learning capability is exploited to achieve fast detection in large dimension systems. The performance of the proposed method is compared with lattice reduction aided detection which is currently the popular choice and the improvement in terms of bit error rate is demonstrated. The sparse formulation of the problem matrix reduces the computational complexity and enables faster detection. The proposed detection algorithm is tailored to address both uncorrelated and correlated channel conditions as well.