Hydrazine In Solution Research Articles

Piezoelectric Pb(Ni,Nb)O3-Pb(Zr,Ti)O3 multilayer ceramics using Cu-Ag electrodes reduced by hydrazine solution treatment

Structure, ferroelectric, and electrostrain characteristics of 0.5Pb(Ni1/3Nb2/3)O3-0.16PbZrO3-0.34PbTiO3 + 0.2 wt% Li2CO3 (PNN-PZT+LC) multilayer ceramics were systematically evaluated to determine the properties of Cu-Ag electrodes reduced by hydrazine solution treatment. Piezoelectric PNN-PZT+LC multilayer ceramics with electrode layers of Cu-Ag core-shell particles were co-fired in air atmosphere at temperatures less than 960 °C. Cu electrode existing of PNN-PZT+LC/Cu-Ag multilayer ceramics entirely oxidized during co-firing. The co-fired specimens were post-treated with hydrazine solution at 120 °C for 30 min to reduce the oxidative electrodes. The specimen co-fired at 950 °C had highly improved values of 2Pr of 62.8 μC/cm2 and 2Ec of 1.9 kV/mm, and the highest d33 * value of 925 pm/V at 2 kV/mm after hydrazine solution reduction process. This confirms that the solution process is excellent for development of cost-effective piezoelectric multilayer ceramics with Cu electrodes.

Copper nanoparticles production by a novel non-dispersive membrane nanoprecipitation process

This study presents, for the first time, a novel route for producing elemental copper nanoparticles using a non-dispersive membrane nanoprecipitation process based on membrane contactors. Copper sulfate solutions ranging between 0.005 and 0.01 M Cu concentration were circulating through a hydrophobic polypropylene flat-sheet membrane, where hydrazine solutions with 1.84–3.64 M were fed by the other side of the membrane. The gradient of hydrazine concentration between both phases was the driving force that promoted the volatilization and transfer of hydrazine through the membrane pores, then reacting with cupric ions to precipitate elemental copper. The effects of copper concentration, hydrazine concentration, and temperature (20–40 °C) in the particle size distribution were assessed. Smaller nanoparticle sizes were obtained at the lowest copper concentration and the highest hydrazine concentration. Thus, the smallest copper nanoparticles were produced under the highest hydrazine/copper molar ratio, reaching values of around 200 nm. Besides, the precipitates showed a surface plasmon resonance, confirming the presence of elemental copper nanoparticles. Therefore, this study opens a new approach to producing metal nanoparticles with perspectives of application in industrial manufacturing, recovering valuable metals from mining effluent treatment, or even hydrometallurgical processes.

Characterization and Antibacterial Potential of Iron Oxide Nanoparticles in Eradicating Uropathogenic E. coli.

Proper management and control measurements are needed to stop the spread of highly pathogenic E. coli isolates that cause urinary tract infections (UTI) by developing new antibacterial agents to ensure the safety of public health. Therefore, the present investigations were used to achieve the synthesis of iron oxide nanoparticles (IONPs) via a simple coprecipitation method using ferric nitrates Fe (NO3)3 as the precursor and hydrazine solution as the precipitator and to explore the antibacterial activity against eradicating Uropathogenic Escherichia coli (E. coli). The synthesized IONPs were further studied using a UV-vis spectrophotometer, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and scanning electron microscopic (SEM) analysis. The maximum surface plasmon resonance peak was observed as absorption at 320 nm in a colloidal solution to validate the synthesis of IONPs. The FT-IR analysis was used to identify different photoactive functional groups that were responsible for the reduction of Fe (NO3)3 to IONPs. The crystalline nature of synthesized IONPs was revealed by XRD patterns with an average particle size ranging as 29 nm. The SEM image was employed to recognize the irregular morphology of synthesized nanoparticles. Moreover, significant antibacterial activity was observed at 1 mg/mL stock solution but after (125, 250, and 500 μg/mL) dilution, the synthesized IONPs showed moderate activity and became inactive at lower concentrations. The morphological and biochemical tests were used to confirm the presence of E. coli in the samples. Furthermore, the minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) were carried out to determine the inhibitory concentrations for the isolated bacteria. The isolated E. coli were also subjected to antibiotic sensitivity testing that showed high resistance to antibiotics such as penicillin and amoxicillin. Thus, the findings of this study were to use IONPs against antibiotic resistance that has been developed in an inappropriate way.

Unveiling the origin of activity in RuCoOx-anchored nitrogen-doped carbon electrocatalyst for high-efficiency hydrogen production and hydrazine oxidation using Raman spectroscopy

Hydrazine-assisted water electrolysis has gained much attention nowadays as an energy-saving strategy for the large-scale production of hydrogen fuel. Regardless, the synthesis of highly proficient bifunctional electrocatalysts remains a major challenge. Metal–organic frameworks (MOF) derived electrocatalysts have recently demonstrated excellent bifunctional activity in water electrolysis. Herein, we developed a new type of Ru-MOF on rod-like Co-MOF (Ru/Co-MOF) microstructures via a two-step solvothermal route. Subsequently, the Ru/Co-MOF was used as a precursor and self-template to synthesize an electrocatalytically active RuO2/Co3O4 anchored nitrogen-doped carbon (RuCoOx@NC) composite via a one-pot pyrolysis–oxidation strategy under atmospheric air. The RuCoOx@NC composite showed an ultralow overpotential of 44 mV for the hydrogen evolution reaction and 255 mV for the oxygen evolution reaction at 10 mA cm−2 in a 1 M KOH solution. Besides, the RuCoOx@NC composite exhibited an ultra-small working potential of − 0.040 V (vs. reversible hydrogen electrode (RHE)) for the hydrazine oxidation reaction at 10 mA cm−2 in a 1 M KOH/0.5 M hydrazine solution. The assembled RuCoOx@NC∥RuCoOx@NC membrane-free overall hydrazine splitting electrolyzer only required ultralow cell voltages of 0.063 and 0.505 V to produce 10 and 100 mA cm−2, with remarkable long-term stability, demonstrating its exceptional bifunctional activity. Ex situ Raman spectroscopy results indicate that both Co3O4 and RuO2 species contribute to the electrocatalytic activity of the RuCoOx@NC composite. This work suggests a potential strategy for developing bifunctional electrocatalytic materials for energy-saving hydrogen production to solve future energy demands.

A novel synthesis of hollow Fe3O4 nanorods with a high saturation magnetization

A novel approach combined Stӧber method with the hydrothermal method was developed for the synthesis of hollow Fe3O4 nanorods by using SiO2 as the template and FeOOH nanorods as the precursor. The investigation of the reaction process confirmed that, as the SiO2 outer layer was gradually dissolved and partially nitrided to Si3N4 in an alkaline hydrazine solution, FeOOH was converted to Fe3O4, resulting in a regular rod-shaped morphology with a hollow structure. The prepared hollow Fe3O4 nanorods had an average length of 430 nm and an average width of 110 nm, and exhibited a high saturation magnetization of 81.6 emu g−1.

Divalent transition metal complexes of nitrogen, oxygen and sulfur containing ligand: design, structural, spectral, pH-metric, theoretical molecular modeling, analytical and mechanism studies

In the present study, the 1-Nicotinoyl-4-phenyl thiosemicarbazide (H2NPT) multidentate nitrogen, oxygen and sulfur containing ligand is being synthesized in a simple single step reaction by condensing 1:1 molar ratio of ethanolic solutions of both phenyl isothiocyanate and nicotinoyl hydrazine. The prepared H2NPT and its complexes with Co2+, Ni2+ and Zn2+ and Cu2+ were characterized by pH-metric titrations, elemental analysis, FTIR, electronic spectra and thermogravimetric (TGA) analyses. The association constant of the ligand and the stability constants of its complexes were calculated by pH-metric measurements in 50% ethanol–water mixture. Also, DFT method was used to draw the geometry of all compounds and the parameters such as bond lengths, bond angles, dipole moment, Frontier orbitals (HOMO, LUMO), MEP and other energetic parameters (optical energy gap, softness, hardness, electronegativity) were evaluated. The prepared H2NPT reacted with Co2+, Ni2+ and Zn2+ and Cu2+ metal ions to form colored precipitates that were readily floated to the surface solution using oleic acid (HOL) surfactant with vigorous shaking of the flotation cell. The heavy metals' concentrations in the dissolved precipitates are determined by flame atomic absorption spectrometry (FAAS). The different parameters affecting the flotation process were thoroughly investigated, viz. pH of sample solution, concentration of ligand, metal ions and HOL, temperature and interfering ions. Nano-gram quantities of Cu2+, Co2+, Ni2+ and Zn2+in 1500-ml samples are quantitatively determined with 1-Nicotinoyl-4-phenyl thiosemicarbazide (H2NPT) at pH 3.0–6.5 for Cu2+ and at 7.0–7.5 for Co2+, Ni2+ and Zn2+. The concentrations of these heavy metals are increased 300-fold. Interferences, on the flotation process, from various foreign ions were avoided by adding excess H2NPT. The mode of chelation between H2NPT and the investigated metal ions is proposed to be through the S, N and/or O atoms of the ligand. The mechanism of flotation is proposed to be due to an electrostatic interaction between the HOL surfactant and the formed metal–ligand complexes through H-bond formation. The proposed multi-element flotation methodology has been utilized for the determination of the analytes in certified reference materials, alloys, synthetic mixtures and in water samples with a recovery % more than 90% and a relative standard deviation (RSD), as a precision < 2%.

Selective Thermal and Photocatalytic Decomposition of Aqueous Hydrazine to Produce H2 over Ag-Modified TiO2 Nanomaterial.

An Ag-modified TiO2 nanomaterial was prepared by a one-pot synthesis method using tetra butyl titanate, silver nitrate, and sodium hydroxide in water at 473 K for 3 h. X-ray diffraction, scanning electron microscopy, and transmission electron microscopy were used to determine the structure and morphology of the synthesized Ag-modified TiO2 nanomaterial. The diffuse reflectance UV-visible and photoluminescence spectroscopy results revealed that metallic Ag nanoparticles decreased the optical band gap and photoluminescence intensity of the TiO2. In addition, the Raman peak intensity and absorbance were increased after Ag modification onto TiO2. The photocatalytic efficiency of the synthesized samples was tested for decomposition of aqueous hydrazine solution under visible light irradiation. The photocatalytic efficiency of Ag-modified TiO2 nanomaterials was higher than that of bare TiO2 and Ag metal NPs due to the synergistic effect between the Ag metal and TiO2 structures. In addition, the surface plasmon resonance (SPR) electron transfer from Ag metal particles to the conduction band of TiO2 is responsible for superior activity of TiO2-Ag catalyst. The Ag-modified TiO2 nanomaterials offered a 100% H2 selectivity within 30 min of reaction time and an apparent rate constant of 0.018 min-1 with an activation energy of 34.4 kJ/mol under visible light radiation.

A coumarin derivative-based turn-on fluorescent probe for real-time applications of hydrazine detection in environment and bioimaging

Increasing the concentration of hydrazine is a major toxic threat to living beings and the environment. Thus, a potential probe was designed, including coumarin-integrated N-(diethylamino)salicylaldehyde (Cou) and 2,4-dinitrobenzoate (DNP), to develop the Cou-DNP probe sensor. The probe can react with hydrazine through the nucleophilic substitution reaction with the elimination of an ester (O–CO-) group besides achieving a “turn-on” fluorescence. This enhanced emission is because of the intramolecular charge transfer (ICT) sensing mechanism that exists between Cou and DNP. Also, the cleavage of an ester bond and the result of coumarin phenol (Cou) were verified through characterizations of 1H NMR, HR-MS, and density-functional theory (DFT) calculations. The application of Cou-DNP was effectively demonstrated by tracking gaseous hydrazine with paper strips; also, soil and actual samples (food, water) were examined to detect hydrazine in the solution phase. Moreover, a time-dependent study was conducted in HeLa cells to monitor the exo- and endogenous (in situ) hydrazine levels using hydrazine solution and isoniazid as a metabolite of hydrazine release, respectively. The probe-pretreated onion epidermal cells were imaged with hydrazine in the time interval of 0–5 min. We anticipate that a probe with the aid of a new recognition unit will provide a replacement for the traditional methods in detecting the toxic analyte hydrazine in real and bio-samples.

Synthesis and Characterization of Schiff Base of 2-Acetyl-5-Methylfuran Glyoxime Hydrazine and its Metal (II) Complexes and Their Evalution for Antibacterial and Antifungal Activities

Two hydrazone Schiff base was synthesized by the interaction of ethanolic solution of antiglyoxime hydrazine with 2-acetyl-5-methylfuran to obtain the Schiff base. The complexes of Mn(II), Fe(II), Ni(II) and Cu(II) and their Schiff base were synthesized and characterized based on solubility, percentage yield, elemental analysis, melting point and decomposition temperature, infra-red spectra (FT-IR), conductivity measurement, magnetic susceptibility and water of crystallisation. The ligand and the complexes were coloured and stable at room temperature. They were soluble in acetone, DMSO, ethanol, methanol, hexane, chloroform, carbontetrachloride, benzene and DMF but insoluble in distilled water. The melting point temperature of the ligand was 118oC while the decomposition temperatures for the complexes were found to be between 295-312oC. The molar magnetic susceptibility of the complexes were in the range of 3.55 x 10-3 – 1.42 x 10-2erg.G-2mol-1. Molar conductance values of 2.17 – 2.87Ω-1cm2mol-1 show non electrolytic nature of the complexes. The spectral data of the ligand showed bands in the range 1581–1607cm-1 revealing the formation of the azomethine group. A band between 760-795cm-1 indicates the metal nitrogen bonds. The elemental analysis of the complexes showed the metal ligand ratio of 1:2 (M:2L). The antibacterial and antifungal studies showed that the complexes exhibited higher antibacterial and antifungal activities than the ligand but lower than the reference drugs.

Synthesis of porous γ-gallium oxide films using refrigerator aging oxidation from gallium nanoparticles

Porous gallium oxide films were tried to synthesize at low temperatures. Ga nanoparticle dispersions were synthesized using ultrasound irradiation in 2-propanol and two films methods were considered. In the case of the spray coating of Ga nanoparticle dispersions and treatment with hydrazine vapor, Ga films were obtained. In the case of depositing Ga nanoparticles on a cover glass and aging them in hydrazine solution at a refrigerator temperature, porous γ-Ga2O3 film was synthesized. This new process of low-temperature aging in a refrigerator using hydrazine solution allows synthesizing porous γ-Ga2O3 film. Generally, the synthesis of oxide ceramics requires high-temperature processing, but this method allows oxidation at low temperatures, such as refrigerator temperatures, making it an energy-efficient process.

Monitoring cell viability in N-nitrosodiethylamine induced acute hepatitis and detection of hydrazine in solution and gas phase with Dual-function fluorescent probes.

The highly toxic N-nitrosodiethylamine (NDEA) and hydrazine (N2H4) caused severe environmental contamination and serious health risks. Herein, we designed the two-photon ratiometric fluorescent probe (Nap-2), emission maximum shifted from 466nm to 571nm, to monitor cell viability of NDEA induced acute hepatitis via esterase activity detection. Furthermore, the probe Nap-2 evaluate the hydrazine (N2H4) content in the solution and gas phase. It is worth mentioning that we used NDEA induced acute hepatitis in the mice and evaluated the negative correlation of esterase activity in the tissue cells and serum with Nap-2. The probe Nap-2 exhibited that acute hepatitis induced by NDEA decreased cell viability. Furthermore, we made convenient test papers using Nap-2 to detect N2H4 in solution and gas phase. After adding N2H4, the fluorescence color changed from blue to yellow and was visible to the naked eye. This work provides a convenient tool and method for evaluating the toxicity of NDEA induced acute hepatitis and detecting N2H4 in the environment.

Optimization of 10 N Monopropellant High Test Peroxide Thruster for Space Applications

Monopropellant thruster is one of the most propulsion system types developed in the space industry. This system uses a single type of propellant that reacts in porous medium catalytic packed bed to generate thrust in the form of hot gases. The last decade, green propellant hydrogen peroxide (H2O2), also known as High Test Peroxide (HTP), thanks to its low cost and easy to store as liquid, is used as an alternative solution of hydrazine which is very toxic and not environmentally friendly. In the current study, hydrogen peroxide monopropellant thruster is investigated for application in the future satellites. A numerical simulation is performed using the Computational Fluid Dynamics (CFD) software ANSYS Fluent in order to simulate fluid flow of hydrogen peroxide in thruster, and the finite volume method was employed for resolving the governing equation. Species transport model is applied in the single-phase reaction simulation using the Eddy Dissipation model (EDM) for turbulence-chemistry interaction. A mathematical approach based on the local thermal non-equilibrium (LTNE) model is used to describe the heat transfer through solid and fluid phases in the packed bed consisting of identical spherical silver particles. Several simulations performed allowed an optimal design of the injector, catalyst bed length and diameter and nozzle geometry, to achieve a 10N monopropellant thruster with hydrogen peroxide at 87.5% concentration.

Synthesis, Characterization and Antimicrobial Activities of Schiff Base Derived From Glyoximehydrazine and Substituted Furan and Their Metal (II) Complexes

A hydrazone Schiff base has been synthesized by the interaction of ethanolic solutions of antiglyoxime hydrazine with 2-acetyl-5-methylfuran to obtain the Schiff base L′. The complexes of Co(II), Ni(II) and Cu(II) of this Schiff base was synthesized and studied. The Schiff base and its metal(II) complexes were characterized based on solubility, percentage yield, elemental analysis, melting point/decomposition temperatures, infra- red spectral (FT-IR), conductivity measurement, magnetic susceptibility and water of crystallisation. Based on the results the prepared Schiff base and synthesized complexes are relatively soluble in most organic solvents but insoluble in distilled water. The melting point temperature of the ligand was 118oC while the decomposition temperature for metal complexes was found to be between 295 _320oC. The molar magnetic susceptibility of the complexes were in the range of 1.91 x 10-3 – 1.46 x 10-2erg.G-2mol-1. The molar conductance values of 2.00 – 3.00ohm-1cm2mol-1 indicating non electrolytic nature of the complexes. The spectral data of the Schiff base showed band at 1641cm-1, revealing the formation of the azomethine group in the Schiff base. A band between 776 and 791cm-1 indicate the metal nitrogen bond. The elemental analysis determination of the complexes and the Schiff base showed the metal ligand ratio of 1:2 (M:2L). The antibacterial and antifungal activities of the Schiff base and the metal(II) complexes were evaluated using disc diffusion method. The antibacterial assay was carried out on three pathogenic bacteria, Salmonella typhimurium, Proteus aureginosa and Staphylococcus aureus, and two fungi viz: Candida utilis and Saccharomyces cerevisiae. The Schiff base and the metal(II) compounds showed some antibacterial and antifungal activity.

Synthesis of Pyridyl‐Imine Complex of Iron(III) as a Fluorescent Sensor for Hydrazine Detection Based on Redox Chemistry

AbstractA six‐coordinated iron(III) pyridyl‐imine complex was synthesized by one‐pot reaction and was demonstrated as a fluorescent sensor for the detection of hydrazine in solution based on the redox reaction. The fluorescence signal generated was attributed to the reduction of the oxidative iron‐center of Fe(III) to Fe(II) by the reductive hydrazine. A good linear relationship for the analysis of hydrazine was obtained with the concentration range of 0.06–0.15 mM (R2=0.99114) in DMF solution. The limit of detection (LOD) estimated was 14.8 μM and the limit of quantitation (LOQ) was 49 μM. Moreover, the color change of the iron(III) pyridyl‐imine complex solution from dark green to reddish brown was able to observed by naked eye, indicating that the Fe(III)‐complex may be also utilized as a colorimetric sensor for hydrazine at millimolar level. The present study demonstrated an interesting fluorescent sensing system based on redox chemistry of an iron(III) complex that generated fluorescence response upon reacting with its redox pair such as the reducing agent hydrazine.

Structural and spectroscopic characterization of the products formed in aqueous solution of hydrazine and maleic acid

• Structural and Spectroscopic studies were carried out using XRD and Spectroscopic techniques. • NBO and HOMO-LUMO energies were estimated. • DFT calculations were accomplished by using B3LYP with 6-311++G(d,p) basis set. • The intermolecular interaction has been evaluated by Hirshfeld surface analysis. The detailed investigation of the structural and spectroscopic characterization of the products formed in aqueous solution of hydrazine and maleic acid is studied in the current research. Single crystal X-ray diffraction inquiry concedes that obtained crystal hydrazinium fumarate ( 1 ) crystallises in the centrosymmetric space group P2 1 /c of the monoclinic system with four molecules per unit cell, whereas maleic hydrazide in the monolactim form ( 2 ) crystallises in the triclinic system with centrosymmetric space group and possess two molecules per unit cell. Further the structure of hydrazinium fumarate is optimized by using density functional theory with B3LYP/6-311++G(d,p) level. Structural and vibrational spectral analysis has been established by both experimental and theoretical method. B3LYP exchange correlational hybrid with 6-311++G (d, p) basis sets are used to assign all modes of vibration and analyse the structure of the molecule in terms of parameters like bond length, bond angle, and dihedral angle. The charge transfer between localised bonds and lone pairs is visualised via NBO analysis. The HOMO–LUMO mappings are presented, revealing the molecule's many charge transfer possibilities. The non-linear attribute of the molecule is described using the dipole moment (μ), polarizability (α), and hyperpolarizability (β) values of the molecule. The Crystal Explorer Ver. 3.1 tool is used to calculate Hirshfeld surface analyses, 2D fingerprint plots, and percentage contributions for several intermolecular interactions in the examined crystal hydrazinium fumarate (1).

Catalytic electro-oxidation of hydrazine by thymol based-modified glassy carbon electrode

In the present, thymol based new organic compounds (4A, 4B and 4C) are designed and synthesized via Steglich Esterification Reactions and Pd-catalyst Sonogashira Coupling Reactions. After isolation and characterization, thymol based hybrid molecules are used for hydrazine (N2H4) electrooxidation reactions as anode catalysts. A variety of metal based anode catalyst have been reported in literature, but this study may be the first study for thymole based hybrid molecules as an anode catalyst in fuel cells. The performance of hybrid molecules was investigated via cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in hydrazine solution. Hybrid 2-isopropyl-5-methylphenyl-4-oxo-4-(5-(p-tolylethynyl)thiophen-2-yl)butanoate (4C) gives the highest performance as 3.66 mAcm−2 (17.24 mAmg−1). Our results displayed that natural products like thymol derivatives may be new generation anode catalyst for fuel cells, and they may be alternative for expensive Pd and Pt based metal anode catalyst.

A smartphone-adaptable chromogenic and fluorogenic sensor for rapid visual detection of toxic hydrazine in the environment

Hydrazine is an essential chemical in industries, but its high toxicity poses great threats to human health and environmental safety. Hence, it is of great significance to monitor the hydrazine in environment. In this work, we presented a chromogenic and fluorogenic dual-mode sensor RA for the detection of hydrazine based on nucleophilic substitution reaction. A linear relationship was obtained between the fluorescence intensity and the concentrations of N2H4 ranging from 0 to 35 μM (R2 = 0.9936). The sensor can determine hydrazine with fast response (within 12 min), low limit of detection (0.129 μM) and high selectivity. RA was successfully used to detect N2H4 in real water samples with good recoveries and the results corresponded to the standard method. Furthermore, the sensor-coated portable test papers were fabricated, which can visually quantify hydrazine solutions with obvious fluorescence transformation from colorless to red. Moreover, RA-loaded papers were used to create a smartphone-adaptable RGB values analytical method for quantitative N2H4 detection.

SYNTHESIS, CHARACTERIZATION AND ANTIMICROBIAL ACTIVITIES OF Ni(II) AND Cu(II) COMPLEXES WITH SCHIFF BASE DERIVED FROM 2-ACETYL-5-METHYLFURAN GLYOXIME HYDRAZONE

A hydrazone Schiff base has been synthesized by the interaction of ethanolic solution of antiglyoxime hydrazine with 2-acetyl-5-methylfuran, to obtain the corresponding Schiff base L. The complexes of Ni(II) and Cu(II) of the Schiff base were synthesized and studied. The Schiff base and its metal(II) complexes characterized based on solubility, percentage yield, elemental analysis, melting/decomposition temperatures, infra- red spectral (FT-IR), conductivity measurement, magnetic susceptibility and water of crystallisation. The synthesized Schiff base and the complexes are coloured and stable at room temperature. Based on the results the prepared Schiff base and synthesized complexes are relatively soluble in most organic solvents but insoluble in distilled water. The melting point temperature of the ligand was 118oC while the decomposition temperature for metal complexes were 308 and 300oC respectively. The molar magnetic susceptibility of the complexes were 3.55 and 2.10 x 10-3 erg.G-2mol-1. The molar conductance values of 2.17 and 2.43ohm-1cm2mol-1 indicating non electrolytic nature of the complexes. The spectral data of the Schiff base showed band of 1584cm-1, revealing the formation of the azomethine. A bands of 791cm-1 indicate the metal nitrogen bond. The elemental analysis determination of the complexes and the Schiff base showed the metal ligand ratio of 1:2 (M:2L). The antibacterial and antifungal activities of the Schiff base and the metal(II) complexes were evaluated using disc diffusion method. The antibacterial assay was carried out on three pathogenic bacteria, Staphylococcus aureus, Staphylococcus epidermidis and Streptococcus pneumonia and two fungi viz: Candida utilis and Saccharomyces cerevisiae. All the Schiff base

Optimization of Phyllanthus emblica L. leaf extract-assisted clearance of hyperbilirubinemia in White New Zealand albino rabbits

All parts of Phyllanthus emblica L. are traditionally used for the treatment of jaundice, inflammation, and diarrhea. The present study was planned to evaluate the P. emblica leaf extract (PELE) assisted clearance of bilirubin in artificially-induced hyperbilirubinemic rabbits. Hyperbilirubinemia was induced in White New Zealand albino rabbits by oral administration of phenyl hydrazine solution (10 mg kg−1 body weight) and an intraperitoneal injection of ursodeoxycholic acid solution (10 mg kg−1 bw). PELE-assisted bilirubin clearance from animals was optimized by a bi-factorial response-surface central composite design with five levels of each of the extract dose (0, 25, 50, 75, and 100 mg kg−1 bw) and sampling period (24, 48, 72, 96, and 120 h). The oral administration of PELE showed a significant (p < 0.05) dose-dependent linear increase in bilirubin clearance from hyperbilirubinemic rabbits. However, the sampling period showed no significant effect on bilirubin clearance. The optimum levels of PELE dose and sampling period for maximum clearance of bilirubin (0.658 mg dL−1) were found to be 94.864 mg kg−1 body weight and 51.12 h respectively. PELE was found to be effective in bilirubin clearance at the observed optimum levels of extract dose and would be a good choice for the management of hyperbilirubinemia.

Effect of Microwave Treatment in a High Pressure Microwave Reactor on Graphene Oxide Reduction Process-TEM, XRD, Raman, IR and Surface Electron Spectroscopic Studies.

Reduced graphene oxide (rGO) was prepared by chemical reduction of graphene oxide (GO) (with a modified Hummers method) in aqueous solutions of hydrazine (N2H4), formaldehyde (CH2O), formic acid (HCO2H) accompanied by a microwave treatment at 250 °C (MWT) by a high pressure microwave reactor (HPMWR) at 55 bar. The substrates and received products were investigated by TEM, XRD, Raman and IR spectroscopies, XPS, XAES and REELS. MWT assisted reduction using different agents resulted in rGOs of a large number of vacancy defects, smaller than at GO surface C sp3 defects, oxygen groups and interstitial water, interlayer distance and diameter of stacking nanostructures (flakes). The average number of flake layers obtained from XRD and REELS was consistent, being the smallest for CH2O and then increasing for HCO2H and N2H4. The number of layers in rGOs increases with decreasing content of vacancy, C sp3 defects, oxygen groups, water and flake diameter. MWT conditions facilitate formation of vacancies and additional hydroxyl, carbonyl and carboxyl groups at these vacancies, provide no remarkable modification of flake diameter, what results in more competitive penetration of reducing agent between the interstitial sites than via vacancies. MWT reduction of GO using a weak reducing agent (CH2O) provided rGO of 8 layers thickness.