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Solar salt is a useful energy storage medium and a heat transfer fluid for concentrated solar thermal applications. The present work explores the use of reduced graphene oxide (rGO) nanostructures as an additive to solar salt, to improve its thermophysical properties. Reduced graphene oxide nanostructures at weight fractions of 0.125 wt% and 0.5 wt% were added to the solar salt, leading to rGO-solar salt composites. The thermophysical characterization experiments revealed that the specific heat in the 0.5 wt% rGO-solar salt nanocomposite was elevated by 6% over the temperature range of 50–270 °C. The time required for complete solidification of 0.125 wt% and 0.5 wt% was reduced by 43% and 49%. In the discharge cycle, the heat transfer rate was amplified by 90% and 138% respectively for 0.125 wt% and 0.5 wt% rGO-solar salt nanocomposites, attributable to thermal conductivity enhancement, specific heat augmentation and heterogeneous nucleation. Thus, rGO-solar salt composites are suitable for use as latent heat thermal energy storage medium in solar thermal applications.

One of the strategies employed to improve the capacitance of reduced graphene oxide is nitrogen doping. Herein, we report the effectiveness of hydrazine hydrate as a nitrogen dopant cum reducing agent. Graphene oxide synthesized by modified Hummer’s method is reduced hydrothermally in the presence and in the absence of hydrazine hydrate and are labeled as NRGO-H and RGO-H, respectively. Hydrothermal reduction of graphene oxide in the presence of a small amount of (6 µL) hydrazine hydrate results in doping of 1.66 atomic weight % of nitrogen as inferred from X-ray photoelectron spectroscopic studies. The effect of nitrogen doping on the morphology and textural properties of reduced graphene oxide is systematically studied using Raman spectroscopy, transmission electron microscope and nitrogen sorption studies. The protruding dopant prevents restacking of graphene layers, resulting in comparatively less number of graphene layers in NRGO-H than in RGO-H. Nitrogen doping also increases number of mesopores and thereby surface area. Owing to Faradaic reaction of the dopant, NRGO-H delivers higher specific capacitance (332 F g−1) than RGO-H (149 F g−1) in aqueous electrolyte (0.25 M H2SO4).

Drawbacks and limitations of recently available therapies to hepatocellular cancer (HCC) devoted the scientist to focus on emerging new strategies. ZnO nanoparticles (ZnONPs) based chemotherapeutics has been emanating as a promising approach to maximize therapeutic synergy facilitating the discovery of novel multitargeted combinations. In the present study we conjugated ZnONPs with ferulic acid (ZnONPs-FAC) characterized by computational, spectroscopic and microscopic techniques. In vitro anticancer potential has been evaluated by assessing cell viability, morphology, ROS generation, mitochondrial membrane permeability, comet assay, immunofluorescent staining of 8-OHdG, Ki67 and γ-H2AX, cell cycle analysis and western blot analysis and in vivo anticancer potential against DEN induced HCC was analyzed by histopathological and immunohistochemical methods. The results revealed that ZnONPs-FAC induces cell death through apoptosis and can suppress the DEN-induced HCC. Our study documents therapeutic potential of nanoparticle conjugated with phytochemicals, suggesting a new platform for combinatorial chemotherapy.

In general, reduced graphene oxide (RGO) is prepared by conventional chemical methods using various reducing agents. The quality and properties of RGO depend on extend of exfoliation and the nature of the reducing agent used for the reduction of graphene oxide (GO). In this work, GO is prepared by modified Hummers’ method and subsequent ultrasonic exfoliation. Then it is hydrothermally reduced to RGO using different amounts (0, 5, 10, 20 and 30 mL) of ethanolic extract of the environmentally threatening invasive weed, Prosopis juliflora. The ethanolic extract of the weed plays multiple roles: (i) reducing GO, (ii) doping nitrogen and (iii) incorporating spacer. The textural properties and surface functionalities (oxygen and nitrogen-based) and thus the capacitance properties of RGO largely depend on the amount of ethanolic extract of the weed used to reduce GO. RGO obtained by reducing GO using a different amount of ethanolic extract of the weed is referred to as RGOXE, where X refers to the amount of ethanolic extract of the weed. The value of specific capacitance follows the order: RGO10E (170 F g − 1) > RGO5E (160 F g − 1) > RGO20E (112 F g − 1) > RGO30E (98 F g − 1) > pristine GO (88 F g − 1). Besides the high value of specific capacitance, RGO10E demonstrates good rate capability (retains 67% of its initial specific capacitance value on increasing the current density from 0.5 to 10 A g − 1) and stable cycle-life (retention of 100% specific capacitance for the tested number of 10,000 cycles). In addition, symmetric supercapacitor fabricated using RGO10E delivers energy density of 4.9 Wh kg−1 at a power density of 496 W kg−1.

Graphene, also referred as reduced graphene oxide (RGO) is prepared by chemical exfoliation method, which delivers specific capacitance of 77 and 40 F g−1 at 0.1 and 1.0 A g−1, respectively in aqueous electrolyte. In order to improve the specific capacitance and high power performance of RGO, composites of RGO are prepared with various carbonaceous ‘spacer’ materials such as acetylene black (AB), activated carbon (AC), multi-walled carbon nanotube (CNT) and carbon derived from polyaniline (C-PANI). Composites of RGO with spacer materials such as AB, AC and CNT is prepared by mechanically mixing RGO with the spacer materials; whereas, RGO composite with C-PANI is prepared by in situ method. These two different preparation methodologies are adopted to realise its effect on the physical and electrochemical characteristics of the composites. Morphological, X-ray diffraction and Raman data confirm the formation of mixture of few and multi-layered RGO stacks. Surface area analysis and morphological data show that the composite prepared by in situ method is beneficial in achieving higher specific surface area and improved mesoporosity. Specific capacitance of RGO and its composites obtained at 0.1 A g−1 decreased in the order: RGO/C-PANI (165 F g−1) > RGO/AC (121 F g−1) > RGO/AB (107 F g−1) > RGO/CNT (95 F g−1) > pristine RGO (77 F g−1). Capacitance retention of RGO and its composite electrodes (in percentage) at 1.0 A g−1, in comparison with the value obtained at 0.1 A g−1 decreased in the order: RGO/AB (84%) > RGO/CNT (75%) > RGO/AC (71%) > RGO/C-PANI (64%) > pristine RGO (52%).

We developed two-coat polymeric nanocomposite coatings for the protection of steel structures from the thermal and corrosive environment. To protect the steel structures, the coating selectivity is crucial; we have chosen the coating such way, the coated surface has low surface energy polymer which has low surface polarity. The polymer nanocomposite coatings were prepared using polydimethylsiloxane with an optimal amount of zirconia nanoparticle. The incorporation of zirconia nanoparticle has extended the thermal stability and efficient corrosion protection of steel substrates. The formulated coatings exhibited a superhydrophobic characteristic with CA-165° and low contact angle hysteresis (

A Novel method of the polyaniline dendritic (PANID) fibers by interfacial polymerization of aniline in chloroform (organic phase) and oxidant of ammonium persulfate (APS), Dodecylbenzene sulfonate (DBSA) (aqueous phase) were controlled by the presence of surface-active dopants. As synthesized dendritic fibers are directly mixed into the organic paint formulation and applied over the steel surface by brush painting. The morphology of dendritic fibers was characterized by Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscope (TEM). Corrosion prevention of the PANID fibers coatings over the Carbon steel surface was determined by using electrochemical impedance spectroscopy (EIS). The impedance values PANID fibers coatings are remained at 10 7 Ώ cm2 even up to 35 day's evaluation whereas the pure epoxy coatings have lost their corrosion protection ability in 3 % NaCl solution. The self-healing ability of PANID fibers coatings cured within 24 h exposure was evaluated by scanning vibrating electrode technique (SVET).

Developing alternative applications for wastes stemming from the processing of industrially applicable crops adds value to industrial crops and limits agricultural land use. Kazak dandelion ( Taraxacum kok-saghyz ; TKS) and Chicory are rich in inulin. In this study, unhydrolyzed inulin-rich chicory and TKS extracts were assessed as substrates for acetone–butanol–ethanol (ABE) production, using different solventogenic Clostridium species/strains. Extracts from chicory and TKS were rich in inulin (∼42 and 36 g/L respectively). In addition to inulin, the chicory extract also contained glucose (3.5 g/L), sucrose (6.2 g/L), fructose (19.5 g/L), and kestose (6.0 g/L), while the TKS extract contained fructose (28.3 g/L), kestose (2.7 g/L) and an unidentified sugar (2.0 g/L). Among the species/strains tested, Clostridium saccharobutylicum P262 demonstrated superior ability to utilize inulin, with at least 86% and 153% higher cell growth and ABE concentration, respectively, on inulin relative to the other species/strains. With pure commercial inulin, TKS and chicory extracts, C. saccharobutylicum P262 utilized 29.0, 25.2 and 40.5 g/L total sugars respectively, and produced 9.7, 8.5 and 12.5 g/L ABE, respectively. However, when fructose, the major product of inulin hydrolysis was used as the sole substrate, cell growth and ABE production by C. saccharobutylicum P262 were at least 74% and 83% lower, respectively, relative to the other species tested. These results demonstrate the suitability of C. saccharobutylicum P262 for butanol production from unhydrolyzed plant inulin and also identify limited fructose utilization as a potential metabolic engineering target for improving the fermentability of unhydrolyzed inulin-rich plant extracts to butanol.

Estuaries receive a considerable amount of pollutants from various sources. Presently an attempt has been made to assess whether the aquaculture discharges and dredging activities alter the ecological conditions of Vellar-Coleroon estuarine complex. The European Water Framework Directive (WFD) established a framework for the protection of marine waters. In this commission, a variety of indices were used, among them, AMBI (AZTI Marine Biotic Index) indices along with multivariate statistical approach is unique, to assess the ecological status by using macrobenthic communities. Keeping this in view, stations VE-1 and VE-4 in Vellar; CE-6 and CE-7 in Coleroon estuaries showed moderately disturbed with the AMBI values ranging between 3.45 and 3.72. The above said stations were situated near the shrimp farm discharge point and sites of dredging activities. The present study proves that various statistical and biotic indices have great potential in assessing the nature of the ecosystem undergoing various human pressures.

Understanding and tuning the wettability of the surfaces are highly intriguing for various applications. The development of stable and transparent coatings over aluminium alloys and glass substrates for making them superhydrophobic and extended oleophobic (lower to the surface tension of 33.4 mN/m (coconut oil)) using a scalable and simple spray painting technique is demonstrated. Fluorinated graphene oxide (FGO, fluorine content of 34.4 atomic weight %), an atomically layered material, modified Polydimethylsiloxane (PDMS) polymer composite is used as the paint for the coatings. The coated films were studied for their surface and compositional features. A water contact angle (CA) of 173.7° (close to the highest ever reported water CA, 175°) is achieved with 60 wt% FGO in PDMS, and the same showing a CA of 94.9° with coconut oil, in conjunction with a low contact angle hysteresis (4°). The work of adhesion with the amount of FGO is studied and the surface energy of FGO containing paints is calculated and compared with the bare paints using Zisman plot analysis.

To evaluate the feasibility of using industrial starchy food wastes as alternative feedstocks for fermentative production of butanol, 34 different food waste samples were obtained from 10 major Ohio food manufacturing companies. Of the food waste samples, 8 were characterized for acetone butanol ethanol (ABE) production. The food waste samples were characterized for moisture, total solids, ash, nitrogen, total organic carbon (TOC), pH, calorific value, minerals and starch content. Results showed that the pH of inedible dough and breadings was in the acceptable substrate pH range (pH 6.2–7.4) for culturing solventogenic Clostridium species, whereas the pH of batter liquid was 4.5, hence, adjusted to pH 6.5 with NH4OH prior to fermentation. Further, batch fermentations by Clostridium beijerinckii NCIMB 8052 using inedible dough, breadings, and batter liquid as substrates generated the following maximum ABE concentrations: 14.4, 14.8 and 15.1 g/L ABE, respectively, which is comparable to the glucose control. Besides, the ABE yield from inedible dough and batter liquid was over 2% better than that of the glucose control. Collectively, these results demonstrate that industrial starchy food waste is a viable alternative substrate for butanol production.

This paper presents a novel design procedure for the coordinated tuning of rotor side converter (RSC) and grid side converter (GSC) controllers of doubly fed induction generator (DFIG) wind turbine system. The RSC and GSC controller parameters are determined by simultaneously optimizing the controller performance indices. The performance indices considered are maximum peak overshoot (MPOSω), settling time (Tssω) of the generator speed and the maximum peak overshoot (MPOSVdc), maximum peak undershoot (MPUSVdc) and settling time (TssVdc) of DC link voltage. The coordinated controller design is carried out in two steps. First step is to arrive at the analytical expression that relates the performance indices and the controller parameters. This is achieved using response surface methodology (RSM) thereby saving significant computational time. In the second step the determination of controller parameters is posed as a constrained multiobjective optimization problem. The constrained multiobjective optimization problem is solved using NSGAII (nondominated sorting genetic algorithm II). The proposed methodology is tested on a sample system with DFIG based WECS. Simulation results demonstrate the effectiveness of the proposed methodology.

The restacking of graphene sheets leading to poor electrical conductivity and reduced surface area strongly affects the capacitance properties of reduced graphene oxide (RGO). Many strategies employed to mitigate the restacking issue include the introduction of spacer materials between the graphene layers, hetero atom doping, compositing with metal oxides, etc. Herein, we report the enhancement of the capacitance properties of RGO by the addition of a small amount of redox active compounds, such as benzoquinone, KI, and NaI in the electrolyte. RGO is prepared by chemical exfoliation of graphite followed by a hydrothermal reduction in the presence of a small amount of hydrazine hydrate. The quality of prepared RGO is examined by microscopic and Raman spectroscopic studies. X-ray photoelectron spectroscopic studies reveal doping of 1.97 atomic weight % of nitrogen in RGO. The specific capacitance values of 105, 244, 322 and 414 F g−1 at a current density of 2 A g−1 are obtained for RGO in 0.25 M H2SO4 and 0.25 M H2SO4 containing 0.05 M of NaI, KI and benzoquinone, respectively. The enhancement in the specific capacitance of RGO is attributed to the reversible redox reaction of the additives. Interestingly, the mechanism of charge storage of RGO in NaI and KI containing electrolytes is different. Owing to rather slow kinetics of redox reaction of electrolyte additives, the rate performance of RGO has slightly compromised in redox active electrolytes.

Superhydrophobic sol–gel nanocomposite coatings with improved oleophobic property were obtained by incorporation of a perfluoroalkylmethacrylic copolymer in a hybrid sol–gel matrix containing fumed silica nanoparticles. The coatings exhibited a water contact angle (WCA) of 158° and contact angle of 146° for ethylene glycol and 113° for lubricant oil. Though the sol–gel nanocomposite coatings in the absence of fluoropolymer were superhydrophobic with WCA of 155°, they were oleophilic with oil contact angle of

Sol–gel superhydrophobic coatings with improved hardness were prepared by embedding fumed silica nanoparticles in a partially condensed hybrid sol of methyltriethoxysilane (MTEOS) and colloidal silica. Fumed silica particles of size 25–30 nm were incorporated in the sol and the mixture was spray-coated on glass substrate. Water contact angle (WCA) of the composite coating increased with increase in silica content of the sol mixture. The concentration of silica in the sol mixture was optimized to obtain robust superhydrophobic coatings with a WCA of 162.5° and a pencil hardness of 5H. The wetting state of water droplet on the sol–gel composite coatings was analysed with both Wenzel and Cassie-Baxter models.

Beta-hemolytic Enterococcus faecalis was isolated from the pericardial fluid obtained from a patient with pyopericardium. The patient was immunocompetent and had mild pleural effusion. He was treated with parenteral co-amoxiclav and amikacin, had undewent pericardiectomy with repeated pericardial aspiration, and recovered completely. To our knowledge, this is the first report of pyopericardium due to E. faecalis .