In the present study, we have tried to establish the correlation between changes in Zeta potential with that of cell surface permeability using bacteria (Escherichia coli and Staphylococcus aureus). An effort has been made to establish Zeta potential as a possible marker for the assessment of membrane damage, with a scope for predicting alteration of cell viability. Cationic agents like, cetyl trimethyl ammonium bromide and polymyxin B were used for inducing alteration of Zeta potential, and the changes occurring in the membrane permeability were studied. In addition, assessment of poly-dispersity index (PDI), cell viability along with confocal microscopic analysis were performed. Based on our results, it can be suggested that alteration of Zeta potential may be correlated to the enhancement of membrane permeability and PDI, and it was observed that beyond a critical point, it leads to cell death (both Gram-positive and Gram-negative bacteria). The present findings can not only be used for studying membrane active molecules but also for understanding the surface potential versus permeability relationship.

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The cart-inverted pendulum is a non-minimum phase system having right half s-plane pole and zero in close vicinity to each other. Linear time invariant (LTI) classical controllers cannot achieve satisfactory loop robustness for such systems. Therefore, in the present work the fractional order PI λ D μ (FOPID) controller is addressed for robust stabilization of the system, since fractional order controller design allows more degrees of freedom compared to its integer order counterparts by virtue of its two parameters λ and μ. The controller parameters are tuned by three evolutionary optimization techniques. In order to select the controller parameters optimally, a novel non-linear fitness function using integral time square error (ITSE), settling-time, and rise time is proposed here. The control algorithm is implemented successfully in real-time. Moreover, stability analysis of the system compensated with a fractional order controller is presented using Riemann surface. Robustness of the physical cartinverted pendulum system towards multiplicative gain variations and plant parameter variations is verified. In this regard, it is shown that the fractional order controller provides satisfactory robust performance in both simulation and real-time system. KEYWORDS cart-inverted pendulum system, FOPID controller, gain margin (GM), non-minimum phase system, Riemann surface, robust stability

nanoparticles of various size (~ 25.8 to 49.7 nm), obtained by a facile oxidation process using Ni(NO 3 ) 2 .6H 2 O, NaOH and sodium hypochlorite as precursor materials at various temperatures (0 o , 25 o , 50 o and 70 o C), is found to remove toxic Cr(VI) from aqueous solution (20 g L -1 ). The structural, morphological, surface charge and chemical compositions of the synthesized samples were characterized by XRD, TEM, zeta potential and EDX respectively. Adsorption capacity is found to be strongly dependent on the size and surface heterogeneity of the synthesized particles and the plausible mechanism for such significant adsorption efficacy is attributed to the sorbate -sorbent electrostatic interaction and shielding of Cr(VI) ions. The adsorption mechanism fits with the Langmuir isotherm model with maximum 60% Cr(VI) removal capacity (20.768 mg g -1 (calculated) and 20.408 mg g -1 (predicted from isotherms)) corresponding to Ni 2 O 3 nanoparticles, prepared at 70 0 C in 3 hours at room temperature. Thermodynamic parameters, obtained from fitting, demonstrate that the adsorption process being endothermic in nature follow pseudo-secondorder kinetic model. The spontaneity of the adsorption process gets reduced with increasing particle size. pH of the solution is observed to have a remarkable effect on the adsorption, giving maximum adsorption at pH = 6. . Please do not adjust marginsPlease do not adjust margins commercially used material for this purpose is the activated carbon or mesoporous carbon due to their high surface porosity. 8, 9 Apart from them, bio-adsorbents are often used as adsorbents in waste water treatment. 10-13 However, they have weak mechanical strength, poor separation capacity and hence they are not very effective in this field. Recently, alternative materials including various oxide based nanocomposites and nanostructure have been synthesized as potential adsorbent of heavy metal ions. 14,15 Thus, with the advancement of technology, newer materials with improved adsorption capacities are being developed.In this context, it has to be mentioned that metal oxides are known to have high adsorption capacity of toxic metals in nanodimensions. Iron and aluminium oxide have been identified to adsorb toxic substances from waste water effectively due to their high surface adsorption ability. [16][17][18] Among different transitional materials, developed so far, NiO has proven itself as an another promising material that shows potential application in battery electrodes, super-capacitors, smart windows, catalysis etc. [19][20][21][22] Nickel, being a transitional metal, possesses variable oxidation states, but most of them are found to be abundant in normal conditions. 23,24 In this context, it has to be mentioned that pseudo hydrate of Ni(III) oxide was reported but their anhydrous form was not observed due to easy transformation of them into NiO on heating. 25 On the other hand, it was established that these higher oxides may possess many interesting properties if obtained in anhydrous form.Accor...

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