Vol. 15(3) September 2011
Fabrication and Properties of PPC/PEO/TiO2 Composite
Polymer Electrolyte for Lithium-ion Battery
Yu Xiao-Yuan, Xiao Min, Wang Shuang-Jin and Meng Yue-Zhong
PEO/PPC/x%TiO2 composite polymer electrolytes (CPEs)
have been prepared by solution casting technique using poly(propylene carbonate)
(PPC) and poly(ethylene oxide) PEO as polymer matrices, nano-TiO2 as filler. The
thermal performance, crystallinity, ionic conductivity, lithium ion transference
number and electrochemical stability of the PEO/PPC/x%TiO2 CPEs were then investigated.
SEM images show that nano-TiO2 particles disperse well in polymer matrix. DSC and
XRD experimental results of all PEO/PPC/x%TiO2 composite polymer electrolytes indicate
that the crystallinity of PEO decreases with increasing nano-TiO2 amount. Therefore,
the results show that the addition of nano-TiO2 particles can enhance the lithium
ion transference number and the ionic conductivity of PEO/PPC/10%LiClO4 composite
polymer electrolytes. The maximum ionic conductivity of 1.4×10－5 S cm-1 at room
temperature, 8×10-3 S cm-1 at 80 oC and the electrochemical stability window of
4.5V (vs Li/Li+) were recorded when the content of nano-TiO2 was 3%. The Lithium
ion transference numbers of PEO/PPC/x%TiO2 composite polymer electrolyte increase
first and then decrease with increasing nano-TiO2 content. The highest lithium ion
transference number (TLi+) was 0.62 for PEO/PPC composite polymer electrolyte with
10% nano-TiO2. The PEO/PPC/3%TiO2 composite polymer electrolytes possess good interfacial
stability with the lithium electrode, making it possible of PEO/PPC/x%TiO2 as the
electrolyte materials for all solid-state rechargeable lithium ion batteries.
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Enzyme-catalyzed Removal of Bisphenol A by Using Herseradish
Peroxidase Immobilized on Magnetic Silk Fibroin Microspheres
Jing Dong, Zhang Kun, Tiantian Tang and Shiyun Ai
The catalytic removal of bisphenol A (BPA) from aqueous
solution with horseradish peroxidase (HRP) immobilized on Silk Fibroin magnetic
microspheres was investigated. To introduce HRP onto the magnetic microsphere, silk
fibroin and poly(amido amine) (PAMAM) were covalently bonded onto the magnetic Fe3O4
nanoparticles to give an aminated magnetic silk fibroin microsphere. HRP was immobilized
onto the aminated microsphere via glutaraldehyde coupling reaction. Upon immobile-zation,
the enzyme showed a broader pH, higher temperature and excellent storage stability.
The optimum condition for the removal of BPA with immobilized HRP was that immobilized
HRP reacted with BPA solution under the temperature of 20~40 C with pH value of
6 for 120 min. Under optimized operational conditions, the degradation efficiencies
of BPA using the native enzyme and immobilized enzyme method were 50% and 64% respectively.
After 4 repeated uses, the immobilized enzyme still retained about 82% of its initial
activity. The results show that the silk–fibroin–PAMAM modified magnetic micros¬pheres
are a promising support for the treatment of wastewaters contaminated by phenolic
compounds.
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Alumina supported Manganese Oxide doped Noble Metal
Oxides for Catalytic Methanation Reaction of Simulated Natural Gas
Wan Abu Bakar W.A., Ali R., Kadir A. A. A., Abd Rahim H.F. and Jue L. C.
Manganese oxide doped noble metal supported on alumina
was prepared for methanation reaction by doping the manganese oxide based catalyst
with noble metals namely ruthenium and palladium via impregnation method. All the
catalysts were calcined at 400ºC and 1000ºC for 5 hours separately. In-house-built
micro reactor with Fourier Transform Infra Red (FTIR) detector and Gas Chromatography
(GC) were used to study the percentage of carbon dioxide (CO2) conversion and also
the percentage of methane (CH4) formation. It was found that the catalyst with Ru:Mn(25:75)-Al2O3
calcined at 1000oC showed 60.21% formation of CH4 at 200oC. FESEM illustrated that
catalyst surface is covered with small and dispersed particles with undefined shape.
The X-Ray Diffraction (XRD) analysis revealed that the catalyst is crystalline.
Moreover, Nitrogen Gas Adsorption (NA) analysis showed that both fresh and spent
catalysts are of mesoporous material with type III isotherm and type H3 hysteresis
loop. Furthermore, fresh catalyst has 84.887 Ǻ pore diameter which is bigger than
used catalyst which is 79.053Ǻ.
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The Effect of Light on the Transformations of Bisphenol
AP in Water
Peng Zhange
Bisphenol AP (4, 4’-(1-Phenylethylidene) bisphenol,
BPAP) is a member of the bisphenol family and is structurally close to bisphenol
A which is a kind of suspected endocrine disruptors. These compounds could be a
threat to the aquatic ecosystems and human health, so its transformation fate in
natural environment was important. In this work, experiments were conducted to study
the transformation of BPAP induced by three kinds of freshwater algae under light.
Results showed that the freshwater algae are capable of promoting the degradation
of BPAP under irradiation. The degradation efficiency of BPAP was increasing with
algae concentration increasing. For example, in the Chlorella vulgaris suspensions,
the photodegradation rate of BPAP was increased from 17% to 25% with algae concentration
ranging from 2.0 × 109 cells•L-1 to 6.0 × 109 cells•L-1. Results showed that the
light had an important role in the chemical transformation of BPAP. Oxidative photodegradation
is a decomposition fate of BPAP in water. The research provides some references
for the fate of phenolic endocrine disruptors in natural water.
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Removal of Fluoride Ions from Aqueous Solution in
a One-Step Process
Huang Ruihua
A novel technology for wastewater treatment was proposed
based on simultaneously synthesis of N-2- hydroxypropyl trimethyl ammonium chloride
chitosan (HTCC)-bentonite and removal of fluoride ions (F-) in a one-step process.
The bentonite modified in the process was characterized by X-ray diffraction (XRD)
and Fourier transforming infrared (FTIR) spectroscopy. The effects of contact time,
temperature, pH and initial concentrations on the removal of F- were investigated.
The removal efficiencies achieved were 84.5 % and 86.3 % within 30 min for F- solutions
with initial concentrations of 20 mg/L and 40 mg/L respectively. The HTCC-bentonite
regenerated with deionized water still retained a high adsorption capacity for F-.
Therefore, the one-step bentonite process could provide a simple, efficient and
economical alternative for removal of high levels of F- from contaminated water.
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Demulsification of Triton X-100, Low-Sulfur Wax Residue
(LSWR), Sorbitan Monooleate (Span 83) and Sodium Dodecyl Sulfate (SDS)-Stabilized
Petroleum Emulsions with a Microwave Separation Method
Abdulbari Hayder A., Abdurahman N.H., Rosli Y.M. and Azhari N.H.
The formation of emulsions during oil production and
processing is a costly problem both in terms of chemicals used and production losses.
For economic and operational reasons, it is necessary to separate the water completely
from crude oils before transporting or refining them. Experimental data are presented
to show the influences of Triton X-100, low-sulfur wax residue (LSWR), sorbitan
monooleate (Span 83) and sodium dodecyl sulfate (SDS) on the stability and microwave
demulsification of petroleum emulsions. It was found that emulsion stability was
related to several parameters including the surfactant concentration, water-to-oil
phase ratio (10–90%), temperature and agitation speed. Based on this study, a possible
emulsion-minimization approach utilizing microwave irradiation is suggested, which
could be implemented in refineries. Compared with conven¬tional heating the use
of microwave heating can significantly enhance the demulsification rate, reaching
over 90 v/v% for the emulsions studied in this work.
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Phytochemical and Bioactivity Studies of Zingiber
amaricans Blume
Riyanto S., Sukari M. A., Rahmani M., Ali A. M. and Shaharudin N.
Phytochemical studies on the rhizomes of Zingiber amaricans
afforded zerumbone1 as the major constituent, together with sterol mixtures containing,
stigmasterol2, β-sitosterol3, cholesterol4 and campes¬terol5. The structures of
the isolated compounds were elucidated using spectroscopic methods. The crude extracts
and isolated pure compounds were examined for their bioactivity against phatogenic
microbes and cancer cell lines. Zerumbone1 shows moderate cytotoxic activity against
human lymphoblastic T leukemia cell.
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The effect of the pH value on the growth and properties
of chemical bath deposited SnS thin films
Anuar Kassim*, Ho Soon Min, Atan Shariff and Md Jelas Haron Department of Chemistry,
Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor, MALAYSIA
Thin films of semiconductors were commonly used for the
fabrication of inexpensive solar cells. The aim of the present study was to investigate
the influence of pH (pH 1.5, 2.5 and 3.5) on the properties of chemical bath deposited
SnS thin films. The differences in the morphological properties of the films were
investigated using atomic force microscopy, meanwhile the optical properties were
studied using UV-Visible spectrophotometer. We observed that the grain size was
relatively uniform, good coverage and thicker films could be obtained at lower pH
value such as pH 1.5. The band gap values were found to be 1.2-1.6 eV for the films
deposited under various pH values.
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Multianalytical characterization of silica-rich megabreccias
from the proposed natural area of Richat (Sahara desert, Mauritania)
Martinez Frias Jesus, Rull Pérez Fernando, Martín-Redondo M.Paz, Huertas Antonio
Delgado, Sampedro Fernández M.Teresa, García-Talavera Francisco, López-Vera Fernando,
Rodriguez-Losada J. Antonio and Salván César Menor
Some terrestrial areas have favourable environmental
features that allow the preservation and scientific study of processes which can
be used as geomarkers. The crater-like Richat structure (Sahara desert, Mauritania)
is a recently proposed protected natural area, which can be considered as one of
these sites. Volcanic, hydrothermal and arid environments merge together, making
easy their investigation in the field and their later characterization by the use
of a set of geochemical and mineralogical techniques (XRD, transmitted and reflected
light microscopy, SEM-EDX, laser-Raman spectroscopy, XRF, ICP-MS and stable isotope
spectroscopy). The study presented here focuses on the spectacular silica-rich megrabreccias
which crop out, as a large and thick lenticular body, at the centre of the Richat
structure. Based on paragenetic relationships, six types of silica-rich megabreccias
were identified. The link between the geochemical and mineralogical characteristics
was established, from macro to micro scale, showing the existence of: a) variable
distributions of the major, minor and trace elements; b) polymorphic phases; c)
micrometric cataclastic features and d) different textural intergrowths and degrees
of crystallinity of some minerals.The oxygen and carbon isotopic signatures of the
carbonates, within the silica-rich megabreccias, point out a meteoric (low-temperature
hydrothermal) origin for the source waters.
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Voltammetric determination of Pb (II) ions by Carbon
Paste Electrode modified with Lemon grass powder
Rajawat D. S. and Satsangee S. P. USIC Remote Instrumentation Lab, Dayalbagh Educational
Institute, Agra 282110, INDIA
Lemon grass powder contains materials with functional
groups which have the ability to bind with metal ions. Lemon grass powder was used
as modifier of carbon paste electrode for voltammetric determination of lead ions
in aqueous samples. Different parameters like electrode composition, different electrolytes,
electrolyte concentration, pH value, deposition time and deposition potential were
optimized for application of lemon grass powder modified electrodes. The use of
0.2M HCl as supporting electrolyte and 10% (w/w) modifier, deposition time 300 sec,
deposition potential -1100 mV and pH 6 gave an optimum current response for lead
(II) solution. Results showed that the fabricated electrode can determine lead with
better sensitivity in aqueous solutions.
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Catalytic-Kinetic Determination of Manganese (II)
by Spectrophotometric Method in Aqueous Acetate Medium
Gazala Mohamed H. Ben Hander Faculty of Science, Chemistry Department, Al-Tahadi
University, Serit, LIBYA
A simple and sensitive spectrophotometric method is reported
for the determination of manganese(II) based on its catalytic effect on the oxidation
of nitrilotriacetatocobalt(II)-benzoate complex by periodate in acetate medium.
The increase in absorbance of Co(III)-product was monitored at 580 nm, pH = 4.99,
I = 0.5 M and T = 25 oC. The kinetics studied have been investigated under pseudo
first order condition by taking large excess of oxidant. The various variables affect
on sensitivity were studied and optimized and a study of interfering ions was also
carried out. The calibration graph was linear in the range of 0.050–0.50 mol dm-3
acetate and (3.0 – 15.0) x10-5 mol dm-3 Mn(II). Mn(I1) in tap water, ground water
and an industrial waste water has been successfully determined by the proposed method.
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Photoremoval of Malachite Green (MG) using Advanced
Oxidation Process
Fouad F. Mohamed*, Puazi Md. Abdul Allah , Asmma Mehdi and Mohamed Baseem
Removal of a commercial dye Malachite Green (MG) from
its aqueous solution over TiO2 suspension and under UV irradiation has been investigated.
The absorption spectra of MG dye indicated that the maximum wavelength 617 nm, almost
kept the same. The process of photodegradation was carried out in aqueous solutions
containing the dye in the presence of TiO2 (Degussa p – 25) upon UV irradiation
(high pressure mercury lamp Radium 125 W). The photocatalytic process used the photogenerated
holes at the surface of TiO2 and hydroxyl radicals at the solution bulk as oxidizing
species for the dyes. Different parameters affecting the photocatalytic degradation
process such as initial dye concentration, TiO2 dosages and amount of H2O2 were
investigated .Results obtained revealed that the dye removal % is inversely proportional
to its concentration but the dye removal % is directly proportional to H2O2. Study
of kinetics has been investigated and the reactions were first order kinetic.
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Influence of Heavy Metals and Surfactants on the Adsorption
of Tetracyclines to Sediment
Jinhua Li, Baoxue Zhou, Bai Xue, Qiulei Mo and Weimin Cai
The widely utilization of pharmaceutical and personal
care products (PPCPs) in the pharmaceutical therapies and agricultural husbandry
has led to the world pollution. Thus, it is of great interest to study the mobility
and fate of PPCPs in the environment. The aim of this study was to investigate the
influence of heavy metal Pb(II), anionic surfactant sodium dodecylbenzenesulfonate
(SDBS), nonionic surfactant Triton X-100 (TX-100) on the adsorption of representative
PPCPs (tetracycline (TC) and oxytetracycline (OTC) on two types of adsorbents. Results
showed that the adsorption isotherms of TC and OTC on two sediments were in good
comparison with Freundlich equation. However, compared to the sediment B without
organic matter (OM), the sediment A with higher OM exhibited the higher adsorption
affinity to TC and OTC. The presence of Pb (II) caused a significant increase on
the TC and OTC adsorption to sediment A due to the formation of ternary complex
between OM ligand groups and tetracycline ligand groups. However, the influence
of Pb (II) on TC and OTC adsorption on sediment B was minimal. The presence of SDBS
increased TC and OTC adsorption on two sediments, which could be due to the significantly
increasing OM content of two sediments via the SDBS adsorption. In contrast, the
nonionic surfactant TX-100 caused a slight reduction on TC and OTC adsorption on
two sediments even at high concentration.
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Toxic Assessment of Potassium Nitrate in Charles Foster
Rats with Emphasis on Histopathology of Vital Organs
Saxena Abhilasha, Dubey Chetan, Gupta Rakhi, Singh Poonam, Bansode F.W., Rawat S.K.,
Singh R. P. and Singh R.K.
Potassium nitrate is a white, powdery compound naturally
present in many leafy green vegetables. Nitrate itself is comparatively non-toxic
but its metabolites may cause a number of health hazards such as nitrite caused
methemoglobinemia. This research work was concerned with the study of midterm (14
days intoxicant) potassium nitrate exposure to Charles foster (CF) rats at the doses
of 0, 45, 90 and 135 mg/kg of body weight. Under these conditions, the body weights
were investigated with special emphasis on the histopathology of vital organs of
rats. No such adverse effect on vital organs was seen which could be related to
nature or dose of potassium nitrate.
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Pyrazoles as Potential Anti-Obesity Agents
Gupta Girish Kumar, Kumar Vikas and Kumar Vinod
Pyrazoles are an important class of heterocycles for
new drug development that attracted much attention in the field of medicinal chemistry.
In literature several pyrazole derivatives have been reported as target structures
and evaluated for their biological activities. This review focuses on the development
of various pyrazole derivatives up to 2010 that possess anti-obesity activity.
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