Cadmium(II)‐Catalyzed C?N Cross‐Coupling of Amines with Aryl Iodides

Cadmium diacetate dihydrate [Cd(OAc)₂⋅2 H₂O] in combination with ethylene glycol catalyzes efficiently the C N cross‐coupling of amines with aryl iodides by a benzyne mechanism. Alkyl, aryl and heterocyclic amines are compatible with this system affording the aminated products in high to excellent yield.     

Automated error correction in IBM quantum computer and explicit generalization

Construction of a fault-tolerant quantum computer remains a challenging problem due to unavoidable noise and fragile quantum states. However, this goal can be achieved by introducing quantum error-correcting codes. Here, we experimentally realize an automated error correction code and demonstrate the nondestructive discrimination of GHZ states in IBM 5-qubit quantum computer. After performing quantum state tomography, we obtain the experimental results with a high fidelity. Finally, we generalize the investigated code for maximally entangled n-qudit case, which could both detect and automatically correct any arbitrary phase-change error, or any phase-flip error, or any bit-flip error, or combined error of all types of error.     

Effect of long-term application of organic amendment on C storage in relation to global warming potential and biological activities in tropical flooded soil planted to rice

The impact of long term organic amendments on the functional microbial activities, soil carbon (C) storage in relation to greenhouse gas (GHG) emission from rice field was investigated in a tropical Aeric Endoaquept. The treatments included unamended control, farmyard manure (FYM), green manure (GM) (Sesbania aculeata), FYM?+?GM and rice straw (RS)?+?GM combination. Our results suggest that the FYM?+?GM treatment has increased the global warming potential (GWP) by 110?% as well decreased the C efficiency ratio by 24?% in comparison to control. On the other hand, under RS?+?GM treatment the soil organic C and total C contents were significantly higher to the tune of 34 and 53?%, respectively. Our studies clearly reveal that the application of RS?+?GM at 1:1 [Nitrogen (N) basis] could probably be the best soil amendment to sequester the soil organic C. Such amendments may not only have practical application value but also lead to higher yield capacity and minimize emission of GHG under flooded tropical rice soil systems.     

Solidification Characteristics and Forgeability of Aluminium Alloy Metal Matrix Composites

The solidification behavior and the forgeability of aluminum alloy (Al 413)/SiCp composites at different sections of a three-stepped composite casting at different weight fraction of SiC particles are investigated. The temperature of the cast composites during solidification has been measured by putting K-type thermocouples, from which the solidification curves were constructed. The forgeability of the as cast MMCs were also measured at different sections (having different modulus) of the casting. The results show that the forgeability of cast metal matrix composites decreases on increasing the weight fraction of SiCp. Experiments have been carried out over a range of particle weight percentage of 5?C12.5?wt% in steps of 2.5?wt%. The solidification curves of aluminum alloy composites have been compared with the unreinforced Al alloy and the results reveal that significant increase in solidification time and decrease in liquidus temperature with the addition of SiCp. The curves also show that the rate of cooling and the solidification time are different at different section of the castings.     

Acylperoxycoumarins as ortho‐C?H Acylating Agent via a Palladium(II)‐Catalyzed Redox‐Neutral Process

An unprecedented palladium(II)‐catalyzed biomimetic aliphatic acyl (‐COR) group transfer was observed from acyl‐α‐peroxycoumarins to the ortho C H sites of directing arenes. Here, the C H activation is associated with a concomitant acyl group transfer via a Pd(II)‐catalyzed, redox‐neutral process. While methods for ortho aroylation (‐COAr) are well documented ortho acylation (‐COR) processes are scarce, hence the present redox‐neutral method is most ideal for o‐acylation of directing substrates.

     

Electrophoretic deposition of doped ceria in anti-gravity set-up

An innovative anti-gravity set-up has been designed and fabricated to consolidate doped ceria powder by electrophoretic deposition. In this set-up, the charged ceramic powders dispersed in non-aqueous suspension moved upward in opposite direction to gravity under the influence of an external applied field and were consequently deposited on the lower face of upper electrode placed horizontally parallel above the counter electrode. Electrophoretic deposition using this innovative technique was found more superior to the conventional electrophoretic deposition using vertically arranged electrodes where a very broad particle size range was used. The deposit thus obtained predominantly contained finer particles which can move relatively easily against gravity. It enabled formation of homogeneous compact films. This paper presents the results of detailed investigation on the effect of different process parameters such as concentration of particles, duration, addition of charge modifier etc. on forming a deposit. A comparison of deposition yield in anti-gravity set-up vis-à-vis conventional set-up is also presented.     

Study of Structural Modification and Fluctuation Induced Electrical Conductivity in \text {YBa}_{2}\text {Cu}_{3}\text {O}_{7-y}+x \text {BaSnO}_{3} Superconductor Composite

A series of \((1-x) \text {YBa}_{2}\text {Cu}_{3}\text {O}_{7-y} + x \text {BaSnO}_{3 }(x = 0.0, 0.1, 0.3, 0.5, 1.0, 2.5, 5.0\,\text {wt}{\%})\) samples were prepared using the solid-state reaction method. XRD graphs confirm the orthorhombic structure in pristine as well as in composite samples. Raman spectra show the presence of all the vibration modes in pure as well as in the composite samples. In addition, some defect-induced modes have also appeared in the higher weight % BSO-added sample, and no loss of apical oxygen O(4) at 500 cm \(^{-1}\) occurs due to BaSnO \(_{3}\) (BSO) addition. Microstructural analysis reveals the unchanged grain size with the incorporation of dielectric BSO particles in the YBCO matrix. Superconducting transition temperature determined from standard four-probe method decreases with the increase of BSO wt%. Excess conductivity fluctuation analysis using Aslamazov–Larkin model fitting reveals transition of two dominant regions (2D and 3D) above \(T_\mathrm{c}\) . 2D to 3D crossover temperature i.e. Lawrence–Doniach temperature that demarcates dimensional nature of fluctuation inside the grains is influenced by BSO incorporation in YBCO matrix.     

Photobiological Production of Hydrogen from Spirulina for Fueling Fuel Cells

Abstract

Natural resources of the world are shrinking day by day with ever increasing population and man's growing need for commercialization of petroleum, natural gas, coal, etc. Therefore, there is a need for finding an alternative fuel that could replace these conventional fuels. Hydrogen seems to be an ideal candidate, since hydrogen is a cleaner source of energy. Fuel cell is a good device that converts hydrogen directly into electrical energy efficiently. However, availability of hydrogen is a problem. There are many conventional methods for producing hydrogen, like thermochemical process, catalytic reforming of hydrocarbons, and electrolysis of water, but these methods are not economical and are mostly non-renewable. Biological means of producing hydrogen offers a renewable source of hydrogen production. Cyanobacteria can split water into hydrogen. Anabaena sp. is found to produce more hydrogen than other species of cyanobacteria; however, if this has to be cultured only for hydrogen production, it may not be commercially viable. Spirulina sp. has a good food value and can produce hydrogen as a byproduct. In order to reduce the cost of the fuel cell, the platinum anode may be replaced by a carbon electrode impregnated with suitable inexpensive metal that may have good catalytic activity such as Co-Al oxide spinel and nickel. Studies towards the photobiological production of hydrogen were undertaken. Hydrogen based fuel cell was assembled and fabricated and these studies are being reported.