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Conversion reaction-based transition metal oxides have been considered as advanced anode materials for lithium batteries because of their high storage capacities; however, the initial lithiation/de...

We report a facile single-step synthesis approach for the development of reduced graphene oxide (rGO) supported copper nanoparticles, which can also perform as a peroxidase enzyme mimicking catalyst. The entire synthesis procedure uses a single reducing agent to reduce graphene oxide and the copper precursor at a relatively lower temperature of 70 °C to generate the Cu-rGO composite, where copper nanoparticles are homogenously decorated on the rGO surface. Morphological and structural analysis shows that the crinkled structure of the rGO protects the copper nanoparticles from excessive oxidation and results in the development of a stable Cu-rGO composite. The as-prepared Cu-rGO composite was studied for its efficacy to perform as a peroxidase mimic by catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB), a peroxidase substrate in the presence of hydrogen peroxide. Cu-rGO was successfully able to catalyze hydrogen peroxide and oxidation reaction of TMB followed by a color change. Our results indicate that the Cu-rGO composite has a largely unexplored potential for application in the development of hybrid sensing and detection systems for hydrogen peroxide, which can also be applied for glucose detection.

Heteroatom functionalities in activated carbons have a positive effect on their electrochemical properties. High surface area, reasonable heteroatom content, and high conductivity are highly appealing for energy storage applications, and imparting all three attributes in a single material is still a formidable task. In this work, this task is addressed by using a routinely discarded protein-rich biomass human hair. It offers a unique prospect as a single precursor for heteroatoms and carbon. Highly functional N and S-co-doped carbons generated by pyrolysis at 800, 900, and 1000 °C yield variable degree of heteroatoms, surface areas, and conductivities. When applied as an electrode material for Li-ion battery and supercapacitor, interestingly, the carbon generated at 900 °C shows better electrochemical performance over its counterparts. A correlative analysis of the structural features and performance is presented.

The Ni1-xFexO (x = 0.00, 0.02, 0.04 and 0.06) nanoparticles are synthesized by chemical precipitation route using polyvinyl-pyrrolidone (PVP) and nitrate metal salts. The results of thermogravimetric analysis (TGA) of the synthesized dried hydroxide powders showed that thermal decomposition occurs up to 500 °C so as to form pure Ni1-xFexO. Therefore, all synthesized samples were calcined at 500 °C for 4 h and then used for further characterization. Energy dispersive X-ray spectroscopy (EDS) of all the samples showed the presence of Ni, O and Fe without any other impurities. From X-ray diffraction (XRD) and transmission electron microscopy (TEM) we could prove that the samples are polycrystalline in nature and are in single phase. The different vibrational modes in Ni1-xFexO (x = 0.00, 0.02, 0.04 and 0.06) nanoparticles were studied by Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). Further, we analyzed the optical response from ultraviolet-visible spectra and Photoluminescence (PL) spectra.

Semi-organic crystals of Glycine Sodium nitrate Calcium nitrate (GSC) with two different molar ratios were grown using slow evaporation technique. Crystals of size 22 × 16 mm were obtained within time period of 3-4 weeks at ambient temperature. The compositional study and purity of the crystals were determined using Energy Dispersive X-ray Analysis (EDAX) and CHN Analyzer. Surface of the crystals was studied at micrometer scale with optical microscopy. These crystals were characterized by powder X-ray diffraction and indexing of diffraction pattern was done based on monoclinic system. We also studied thermal properties of these crystals using TGA/DTA/DTG analysis. From UV-Vis spectra we could observe wide transparency window from these crystals in the visible region, which can be useful for opto-electronic applications.

Zirconocene dichloride (Cp2ZrCl2) in the presence of ethanol is found to be a highly efficient catalyst for the one-pot synthesis of structurally diverse 2-substituted benzimidazole derivatives by reaction of o-phenylenediamine and aromatic aldehydes at ambient temperature.

Au-multiwall carbon nanotube (Au-MWCNT) composites with well-dispersed Au-nanoparticles (NPs) are prepared using a simple and efficient solution method and applied as electrode materials for electrochemical capacitors. Au NP loading is varied, and electrochemical performance of the Au-MWCNT composites is investigated using cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS) measurements. Au NP decoration boosts the supercapacitor performance of the Au-MWCNT composite compared with bare MWCNTs. Composite with lower loading of 10 wt% Au loading displays higher specific capacitance (105 F g − 1 ) compared with bare MWCNTs (48 Fg − 1 ) at a current density of 0.8 A g − 1 , demonstrating that the Au NP decoration significantly enhances the supercapacitor performance of the composite despite no participation of Au in faradic reaction. By varying the metal loading of the composites, it is revealed that lower metal loading with smaller particle size is more effective in enhancing the capacitance behavior of the composites compared with ones with higher metal loading. This behavior is mostly related to the interactions that take place at metal-graphitic interface which may include lowering of Schottky barriers and work function of the metal.

Malaria remains an overwhelming problem with around 214 million cases reported worldwide each year. It remains a major health problem in the tropical developing countries and India accounts for 70% of the total malaria incidence in the Southeast Asia region. Even though, artesunate, a novel drug used in the treatment of chloroquine-resistant cases of Plasmodium falciparum infection causes transient transaminitis (elevation of alanine and aspartate transaminases), hepatitis and hepatic encephalopathy are very rare. We encountered a child with falciparum malaria, who accidently ingested artesunate tablets (16 mg/kg) and developed hepatic encephalopathy with clinical and biochemical improvement in a matter of 4 to 5 days. There are only a few reports of children with malaria developing hepatic encephalopathy, with or without coinfection with hepatotropic viruses. Also, there are no reports of hepatic encephalopathy secondary to artesunate overdose, creating a dilemma in diagnosis and management.

An efficient, selective and green route for the synthesis of 2-substituted Benzothiazole derivatives (3a-i) developed by the reaction of 2-aminothiophenol (1) and various aromatic aldehydes (2a-i) using oxalic acid dihydrate: proline low transition temperature mixture (LTTM) as green reaction medium at room temperature. The attractive features of this protocol are simple reaction conditions, recyclability and reusability of the LTTM, good product yield and easy workup procedure. The method is operationally simple and ecofriendly.

Herein, a unique approach to dispose of human hair by pyrolizing it in a regulated environment is presented, yielding highly porous, conductive hair carbons with heteroatoms and high surface area. α-keratin in the protein network of hair serves as a precursor for the heteroatoms and carbon. The carbon framework is ingrained with heteroatoms such as nitrogen and sulfur, which otherwise are incorporated externally through energy-intensive, hazardous, chemical reactions using proper organic precursors. This judicious transformation of organic-rich waste not only addresses the disposal issue, but also generates valuable functional carbon materials from the discard. This unique synthesis strategy involving moderate activation and further graphitization enhances the electrical conductivity, while still maintaining the precious heteroatoms. The effect of temperature on the structural and functional properties is studied, and all the as-obtained carbons are applied as metal-free catalysts for the oxygen reduction reaction (ORR). Carbon graphitized at 900 °C emerges as a superior ORR electrocatalyst with excellent electrocatalytic performance, high selectivity, and long durability, demonstrating that hair carbon can be a promising alternative for costly Pt-based electrocatalysts in fuel cells. The ORR performance can be discussed in terms of heteroatom doping, surface properties, and electrical conductivity of the resulting porous hair carbon materials.

A simple and new protocol for rapid and highly efficient synthesis of substituted tetrahydropyridines developed by multicomponent reaction of one molecule of ethyl acetoacetate, two molecules of various substituted aromatic aldehyde and two molecules of aniline in the presence of Cu(OTf)2 as catalyst. The synthesized compounds screened for anti-inflammatory activity by the detection of MMP-2 and MMP-9 using Gelatinase Zymography. The attractive features of this protocol are mild reaction conditions, reusability of the catalyst, easy workup procedure and improved synthesis which avoid chromatographic purification.

Platinum counter electrodes in DSSC are generally prepared by thermal reduction method. Poor control over Pt particle size, agglomeration and bad adhesion to the transparent conducting substrate, are some of the shortcomings affecting overall efficiency of the cell. In order to achieve better dispersion and control over the particle size, we explored direct deposition of metal nanoparticles (NPs) from their precursor solution onto the FTO glass substrate by using a simple and effective urea-assisted homogenous deposition (HD) method. This method works at substantially lower temperature for hydrolysis of urea and uses mild reducing agent, ethylene glycol (EG), giving better control over particle size along with better adhesion and negligible agglomeration compared to the thermal reduction method. DSSC prepared from such Pt counter electrode exhibited much enhanced photovoltaic performance compared to ones prepared by thermal and EG reduction alone, with better light-to-electricity conversion efficiency of 9.34% under one sun illumination. This excellent conversion efficiency is attributed to the uniform dispersion and smaller size of the Pt NPs prepared by the novel, combined urea-assisted HD–EG synthesis method.

Enzyme mimics have garnered considerable attention as they can overcome some serious disadvantages associated with the natural enzymes. In recently developed sphere and rod shaped iron oxide peroxidase mimic nanoparticles, the influence of physical parameters such as shape, size and surface area on the catalytic performance was not clearly demonstrated. In order to better understand the influence of physical parameters on the enzyme mimic activity of iron oxide nanoparticles, the present study was initiated using three different shaped hematiteα-Fe2O3 nanostructures, particularly hexagonal prism, cube-like and rods as model systems. A comparative account of kinetic parameters (Km, Vmax and Kcat) of the peroxidase mimic activity by the various α-Fe2O3 nanostructures indicated that the enzymatic potential of these nanoparticles increased from hexagonal prism to rods, via cube-like, suggesting that one-dimensional particles act as a more efficient enzyme mimic system compared to their multi-dimensional counterparts. Surface area is likely to be a key physical aspect responsible for the enzyme mimic activity. Interestingly, however, particles with lower surface area showed better catalytic performance in the case of one-dimensional rod structure. Upon further analysis of the one-dimensional rods, additional physical properties such as porosity and pore shape also seem to have a significant contribution to their catalytic activity.

Several studies have demonstrated that nanoparticles (NPs) have toxic effects on cultured cell lines, yet there are no clear data describing the overall molecular changes induced by NPs currently in use for human applications. In this study, the in vitro cytotoxicity of three oxide NPs of around 100 nm size, namely, mesoporous silica (MCM-41), iron oxide (-NPs), and zinc oxide (ZnO-NPs), was evaluated in the human embryonic kidney cell line HEK293. Cell viability assays demonstrated that 100 MCM-41, 100 , and 12.5 ZnO exhibited 20% reductions in HEK293 cell viability in 24 hrs. DNA microarray analysis was performed on cells treated with these oxide NPs and further validated by real time PCR to understand cytotoxic changes occurring at the molecular level. Microarray analysis of NP-treated cells identified a number of up- and down-regulated genes that were found to be associated with inflammation, stress, and the cell death and defense response. At both the cellular and molecular levels, the toxicity was observed in the following order: ZnO-NPs > -NPs > MCM-41. In conclusion, our study provides important information regarding the toxicity of these three commonly used oxide NPs, which should be useful in future biomedical applications of these nanoparticles.

The intramolecular cyclization of the esters of salicylaldehyde, O-hydroxyacetophenones, methyl salicylate, and 2′-hydroxy chalcones by potassium hydroxide in pyridine leads to a short and convenient synthesis of 3,4-disubstituted coumarins. Twenty 3-phenyl coumarins were synthesized in 80–90% yields. No other by-product, such as 2-benzylchromone or β-diketones, was observed the reactions. The mild reaction condition involves the removal of more acidic benzylic proton, which leads to a relatively cheap, nontoxic, metal-free method for the synthesis of 3-aryl-4-substituted coumarins.

A convenient method for deprotection of allyl carboxylic esters has been developed by using the inexpensive and environmentally friendly reagent dimethylsulfoxide–iodine. A variety of carboxylic esters were deprotected to the carboxylic acids. This method is more efficient and operationally simple in comparison to methods using transition metal complexes.

The Ni1−x Cu x O (x = 0, 0.05, 0.10, 0.15) nano-crystalline are synthesized by chemical precipitation route using metal chloride salts and polyvinyl-pyrrolidone (PVP). Thermal decomposition results of dried hydroxide powder showed the weight loss up to 500 °C. Therefore, synthesized samples were calcined at 500 °C for 4 h and used for further characterization. The EDAX results confirm the purity of the synthesized nanomaterials. The structural phase and morphology of the calcined powders were investigated by powder XRD and TEM techniques respectively. The XRD results show the cubic rock salt fcc structure with Fm-3m space group. The TEM results reveal the reduction size of nanomaterials on doping of Cu in NiO. The synthesized samples are characterized by Raman and photoluminescence spectroscopy to study their vibrational and luminescence properties respectively.

Background: Cardiovascular disease is a common cause of death in developed countries and also is a rising trend in developing countries. Aim: The objective of this study was to compare lipid profile and atherogenic indices in term and preterm neonates. Methods: A total of 60 neonates were selected which were grouped on the basis of gestational age and birth weight. Umbilical venous blood was collected from them. Lipid profile (total cholesterol, LDL cholesterol, HDL cholesterol, VLDL cholesterol, triglycerides), apolipoproteins (apo B and apo A-I) and atherogenic index were evaluated and compared. Student- t test (unpaired) was applied to test the significance. Results: Mean serum cholesterol and LDL was significantly high in preterm .Mean TC / LDL ratio of preterm group 3.17, term 2.64 (p< 0.006).Mean Apolipoprotein A-1 in preterm 78.37 mg/dl, term 76.51 mg/dl (P

The aim of present study was to develop and validate a dissolution test method for film coated formulation containing tapentadol and paracetamol, using RP-HPLC method. The optimized dissolution conditions includes USP apparatus II at a paddle rotation rate of 50 rpm and 900 ml of 6.8 pH Phosphate buffer at 37°C± 0.5°C. Under these conditions, the in vitro release profiles of tapentadol and paracetamol showed good results. The drug release was estimated by RP-HPLC using column Hyperchrom ODS 5µ C18 (250 x 4.6mm, 100°A), detection wavelength 217 nm having the flow rate 1.0mL/min using ACN: Potassium dihydrogen phosphate buffer in the proportion of 35:65and adjusted pH to 2.8 with orthophosphoric acid. The method validation was carried out as per for USP guidelines and it was found that the results obtained by proposed method for dissolution test for tablet formulation containing Tapentadoland paracetamol are reliable, precise and accurate. Hence it was routinely adopted for dissolution analysis of the said drugs in the formulation. Keywords: Dissolution testing, Tapentadol, Paracetamol, Validation, High performance liquid chromatography

A new approach is described to produce an efficient electrode material for biofuel cells using flexible carbon cloth (FCC) and hollow core-mesoporous shell carbon (HCMSC) nanospheres as bio-anode materials. The bio-electrochemical activity of glucose oxidase (GOx) enzyme adsorbed on this bio-anode was evaluated, with the maximum anodic current density varying from 80 microA cm(-2) to 180 microA cm-2 for glucose concentrations up to 5.0 mmol L(-1) for the FCC modified electrode with HCMSCs. The open circuit cell voltage was E(0) = 380 mV, and the catalytic electro-oxidation current of glucose reached 0.1 mA cm(-2) at 0.0 V versus Ag/AgCl. This new system employing HCMSC-based FCC is promising toward novel bio-anodes for biofuel cells using glucose as a fuel.

The intramolecular cyclization of the esters of salicylaldehyde, O-hydroxyacetophenones, methyl salicylate, and 2′-hydroxy chalcones by potassium hydroxide in pyridine leads to a short and convenient synthesis of 3,4-disubstituted coumarins. Twenty 3-phenyl coumarins were synthesized in 80–90% yields. No other by-product, such as 2-benzylchromone or β-diketones, was observed the reactions. The mild reaction condition involves the removal of more acidic benzylic proton, which leads to a relatively cheap, nontoxic, metal-free method for the synthesis of 3-aryl-4-substituted coumarins.

The characteristics of heat-stable, ethanol-precipitable antigens (BE) of adrenals and muscle tissues of cattle, buffalo, sheep, goat and pig were studied. The antigens were subjected to protein analysis. The distribution patterns of the antigens employing sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) as well as polyacrylarnide gel isoelectric focusing revealed that the heat-stable antigens of a dreds contained only one component corresponding to troponin T, whereas muscle BE showed associated low molecular weight components along with troponin T as major component. Negative results of thymol-H2SO4 staining of SDS-PAGE gels indicated that the thermostable antigens did not belong to the mucoprotein class.

Persistence Photo Conductivity (PPC) in Ni-doped Cadmium Sulphide [Cd1−xNixS, (x=0, 0.03, 0.05 and 0.20)] thin films were investigated. While the morphology of the films prepared by Spray Pyrolysis Technique (SPT) were studied using Atomic Force Microscopy (AFM), the PPC has been studied using a low temperature two probe resistivity set up with a photo-diode excitation. Note worthy changes in the morphology were observed upon Ni substitution and is attributed to the strain induced upon substitution. The simple resistivity analysis shows an evolution to a highly resistive state upon increasing the Ni content and may be attributed to the local oxide formation. Ni doping enhances the photo sensitivity of the films that may be tuned for technological applications.

26-faceted truncated cuboctahedrons of maghemite (γ-Fe2O3) nanocrystals are grown via 14-faceted truncated octahedrons through simple and effective flame pyrolysis method by direct burning of ferrocene in different solvents in an alcohol lamp. Systematic investigations showed that the solvent plays an important role in the formation and development of the polyhedral maghemite nanocrystals. The maghemite polyhedral structures are characterized by XRD, TEM and HR-SEM analysis in detail and on the basis of these, the crystal growth mechanism is discussed. Some solvents generated maghemite–carbon composites by encapsulation of maghemite polyhedron by graphene-like layered carbon surrounded by amorphous carbon shell. The as-prepared maghemite–carbon composite showed superior storage performance when tested for Li-ion battery applications. Compared to pure maghemite, the carbon composite exhibited a stable discharge capacity of ∼400 mA h g−1 even after 50 cycles, while the discharge capacities of bare maghemite dropped to ∼100 mA h g−1 after 20 cycles.

A new formula for calculating the calorific value of coal from its ultimate analysis has been obtained by regression analysis of a data bank consisting of data on 775 samples of U.S. coals of all ranks. It yielded zero average difference between observed and calculated values and a standard deviation of 129 Btu/lb (300 kJ/kg). Neither average difference nor standard deviation varied much with rank of the coal. The Dulong, Mott-Spooner, Boie, and Grummel-Davies formulae were also tested with the data but gave substantially poorer results. The new formula has been substantiated with data from other laboratories and with data on chars. The distribution of variance, attributable to variability of mineral matter, variability of coal organic matter not related to rank, and variance of laboratory determinations was estimated. Use of the formula to monitor performance of a laboratory is illustrated, as is modification to obtain maximum precision in heat balance calculations on a coal conversion process.

A silverside of buffalo was cut in 15 equal-sized steaks and divided into five groups, each group containing three steaks. The steaks from groups 1,2,3 and 4 were treated with 1, 2, 3 and 4% acetic:lactic acid combinations, respectively, and the fifth group was kept as a control. Similar treatments were also given with acetic: propionic acid mixtures. The microbial analysis and changes in colour and odour were noted at 0, 24, 72 and 168 h. The bacteriostatic and bacteriocidal action of the acid mixtures increased with increasing concentration but the effect was reduced as the time advanced. Both acid mixtures had pronounced antibacterial effect on gram negative organisms than gram positive ones. The 3% acetic: lactic acid combination showed reduction in bacterial numbers without affecting the colour and odour of buffalo meat and is recommended for decontamination and preservation of meat for up to seven days at refrigeration temperature (7 ± 1°C).

Process optimization is one pathway to maximizing strength of a given alloy. Thixomolding® is a semi-solid casting process that combines pores reduction with a typical bimodal grain size distribution that can lead to enhanced strength. AZ91D and AZX911 were processed via Thixomolding® using two different processing conditions to change fraction solid of primary particles at the point of injection into the mould. The tensile properties, creep resistance and corrosion behaviour of the alloys were investigated. The creep resistance was measured in the range of 135–150 °C for stresses of 50–85 MPa. The corrosion behaviour was measured via hydrogen evolution for the two alloys and was smaller than that for die-cast AZ91. The AZX911 alloy showed improved creep resistance compared to the AZ91D. The differences in the property profile of the chosen alloys are correlated with their chemical compositions as well as with different microstructures obtained through the different processing conditions.