01730nas a2200193   4500008004100000022001400041245004700055210004700102260007100149300001400220490000700234520111100241100002301352700001401375700002001389700002101409700002601430856008001456       2011                        eng d  a0888-588500aFractal impeller for stirred tank reactors0 aFractal impeller for stirred tank reactors  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUN  a7667-76760 v503 a<p>Stirred tank reactors are used for variety of applications at different scales of operation. The conventional impellers tend to develop regions having nonuniform energy dissipation rates in the stirred reactor. In this work, we propose a novel fractal impeller, which helps in reducing such nonuniformities and help develop a uniform randomness throughout the reactor. The impeller geometry is discussed in detail. Experimental measurements of the power consumption, mixing time, suspension quality, and the ability for gas dispersion were carried out, and the performance is compared with the conventional impellers. The impeller is seen to have a low power number, and it can generate a uniform suspension of particles even at relatively lower impeller speeds and can efficiently disperse gas into liquid to yield relatively higher gas hold-up values. The Fourier analysis of the power consumption time series data indicates that no specific prominent frequency events exist in the reactor, and the spectrum showed several frequency events to exist in the reactor with almost identical prominence.</p>1 aKulkarni, Amol, A.1 aJha, Neha1 aSingh, Abhishek1 aBhatnagar, Sumit1 aKulkarni, Bhaskar, D.  uhttps://library.ncl.res.in/content/fractal-impeller-stirred-tank-reactors-002471nas a2200301   4500008004100000022001400041245011900055210006900174260000800243300001600251490000700267520146700274653001401741653003601755653001801791653000801809653001801817100002501835700002201860700002001882700002201902700001501924700002801939700002501967700002001992700002902012856012802041       2022                        eng d  a1944-824400aImprovement in oxygen evolution performance of NiFe layered double hydroxide grown in the presence of 1T-Rich MoS20 aImprovement in oxygen evolution performance of NiFe layered doub  cJUL  a31951-319610 v143 a<p>
	NiFe layered double hydroxide (NiFe LDH) grown in the presence of MoS2 (rich in 1T phase) shows exceptional performance metrics for alkaline oxygen evolution reaction (OER) in this class of composites. The as-prepared NiFe LDH/MoS2 composite (abbreviated as MNF) exhibits a low overpotential (eta(10)) of 190 mV; a low Tafel slope of 31 mV dec(-1); and more importantly, a high stability in its performance manifested by the delivery of current output for 45 h. It is important to note that this could be achieved with an exceedingly low loading of 0.14 mg cm(-2). The mass activity of this composite (97 A g(-1)) is about 14 times greater than that of the conventional RuO2 (7 A g(-1) ) at eta = 200 mV. When normalized with respect to the total metal content, a mass activity of 1000 A g(-1) (eta = 300 mV) was achieved. Impedance analysis further reveals that the significant reduction in charge-transfer resistance and hence high current density (5 times greater as compared to NiFe LDH at eta = 300 mV) observed for MNF is associated with interfacial adsorption kinetics of intermediates (R-1). Significant enhancement in the intrinsic activity of MNF over LDH has been observed through normalization of current with the electrochemically active surface area. Computational studies suggest that the Ni centers in the composite act as the active sites for OER, which is well-corroborated with the observed postreaction appearance of Ni3+ species.</p>
10aImpedance10aLDH-MoS2 hybrid electrocatalyst10amass activity10aOER10aoverpotential1 aChakraborty, Soumita1 aMarappa, Shivanna1 aAgarwal, Sakshi1 aBagchi, Debabrata1 aRao, Ankit1 aVinod, Chathakudath, P.1 aPeter, Sebastian, C.1 aSingh, Abhishek1 aEswaramoorthy, Muthusamy  uhttps://library.ncl.res.in/content/improvement-oxygen-evolution-performance-nife-layered-double-hydroxide-grown-presence-1t