3.1 a simple and effective method of the synthesis of αααα...

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3.1 A simple and effective method of the synthesis of αααα-Fe2O3 nanoparticles :

Iron oxides belong to the most abundant minerals and occur with a large variety of

stoichiometries, structures, and properties. The more important ones are FeO (wustite), λ-

Fe2O3 (maghemite), α-Fe2O3 (hematite), and Fe3O4 (magnetite) with rock-salt, vacancy rich

inverse spinel, corundum, and inverse spinel structures, respectively; the two former ones

being thermodynamically less favorable and α-Fe2O3 being the most oxidized one. Iron

oxides are widely used in industry as catalysts or catalyst supports. Metal-oxides constitute an

important class of materials that are involved in environmental science, electrochemistry,

biology, chemical sensors, magnetism and other fields. One of their most important

applications is heterogeneous catalysis. Heterogeneous catalysts based on magnetic mixed

iron oxides (MO-Fe2O3; M: Fe, Co, Cu, Mn) were used for the decolorization of several

synthetic dyes like bromophenol blue, chicago sky blue, Cu-phthalocyanine, eosin yellowish,

evans blue, naphthol blue black, phenol red, poly B-411, and reactive orange 16. All the

catalysts decomposed H2O2 yielding highly reactive hydroxyl radicals, and were able to

decolorize the synthetic dyes. The most effective catalyst FeO-Fe2O3 (25 mg mL-1 with 100

mmol L-1 H2O2) produced more than 90% decolorization of 50 mg L-1.bromophenol blue,

chicago sky blue, evans blue and naphthol blue black within 24 h [1-14]. Aluminium

stabilized mixed metal oxide of copper and iron serve as an active catalyst for the nitration of

benzene in solid–liquid phase reaction, using 69% nitric acid as a nitrating agent. The

reaction was carried out with 100% selectivity towards nitro benzene [15]. Titania- and iron

oxide-supported gold catalysts have been used for the hydrogenation of propyne [16]. Fe2O3,

Mn2O3, and calcined physical mixtures of both ferric and manganese oxides with alumina

and/or silica gel have been used for the catalytic dehydration of ethanol [17]. The catalytic

behaviour of α-Fe2O3-based catalysts has been investigated for the toluene ammoxidation

reaction [18]. Iron (III) hydroxide has been used for the photooxidation of 2-aminophenol in

aqueous solution [19]. The partial oxidation of propane to formaldehyde using uranium

mixed oxide catalysts has been performed. Outstanding results for the selective oxidation of

propane and propene to formaldehyde were obtained using Fe/U catalysts [20]. An efficient

and selective acylation of alcohols and amines employing carboxylic acids as acylating

agents has been done by the metal oxide containing activated carbon catalyst, Catalyst was

synthesized by carbonization of organic ion-exchangers after incorporation of Fe3+ ions with

exchangeable cations present in resin [21]. Dehydrogenation of ethylbenzene has been

studied using potassium-promoted iron oxide as catalyst [22]. The sensitized photocatalytic


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degradation of mono-, di- and trichlorophenols with aqueous suspensions of α-Fe2O3 and α-

FeOOH has been reported [23]. The oxidative dehydrogenation of propane on α - Fe2O3 has

been done in the presence and absence of tetrachloro methane at 723K [24]. Intramolecular

condensation reactions of pentamethylene and hexamethylene glycols over iron oxide has

been studied [25]. Catalysts consisting of sodium-promoted silica gel-supported iron oxide

has been found to catalyze the gas phase epoxidation of propene by nitrous oxide.

Selectivities to propene oxide of 40–60% at propene conversions in the range of 6–12% were

observed [26]. The catalytic conversion of benzoic acid to phenol in the presence of water

and oxygen was studied in the vapor phase over nickel oxide on various supports, like iron

oxide and silica [27]. Fine particle iron oxide based aerogels have been used as catalyst for

the partial oxidation of methanol [28]. Oxidation of benzoic acid has been studied via Fenton-

like reaction using an innovative supported γ-FeOOH catalyst [29]. Iron oxide and iron

carbide have been used as catalyst for the dehydration of tertiary alcohols [30]. Selective

reduction of nitro groups in aromatic azo compounds has been done in the presence of an iron

oxide/hydroxide catalyst [31]. Reduction of aromatic nitro compounds with hydrazine

hydrate in the presence of an iron oxide hydroxide catalyst has also been studied [32].

Decolorization of synthetic dyes by hydrogen peroxide with heterogeneous catalysis by

mixed iron oxides has been studied [33-34]. Nanosized iron oxides have considerable

attention due to their unique magnetic properties (superparamagnetism, high coercivity, low

curie temperature, high magnetic susceptibility, non-toxicity, biocompatibility and low cost

of production, which allows their usage in various nanotechnology applications in a broad

range of disciplines. Magnetic nanoparticles are also important in biomedical applications

e.g. magnetic bioseparation [35], magnetic target drug delivery [36], hyperthermia [37],

magnetic resonance imaging [38], magnetofection [39]. These particles have an ability to

interact with various biological molecules in different ways due to their superparamagnetic

properties, high specific area and wide choice of surface functionalization. In the present

work we have synthesized α - Fe2O3 nanoparticles by simple aqueous precipitation using

ammonia as precipitating agent. This method involves a simple, cheap and one step process

for synthesis of Fe2O3 nanaoparticles. The obtained particles of Fe2O3 have size from 15-42

nm. The synthesized nanoparticles were characterized by XRD, TGA/DTA, Magnetic

susceptibility and TEM


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3.1.1 Results and discussions:

X-ray studies:

X-ray diffraction of synthesized oxide is shown in Figure (3.1). X-ray diffraction pattern of

pure iron oxide indicated that iron oxide is in the form of α - Fe2O3 [Fig- 1]. The X-ray

diffraction plot, shown in Fig. (3.1), shows peaks only due to α - Fe2O3 and no peak are

detected due to any other material or phase indicating a high degree of purity of the as-

synthesized sample. The broadening of the X-ray diffraction lines, as seen in the figure

reflects the nano-particle nature of the sample. In X-ray diffraction, some prominent peaks

were considered and corresponding d-values were compared with the standard [JCPDS file

No. 85-0987] [Table-3.1]. X-ray diffraction shows that metal oxide is pure α - Fe2O3 having

rhombohedral structure. Sharpness of the peaks shows good crystal growth of the oxide

particles. Average particle size (t) of the particles have been calculated using from high

intensity peak using the Debye-Scherrer equation

t = Kλ/ B cos θ

Where t is the average crystallite size of the phase under investigation, K is the Scherrer

constant (0.89), λ is the wave length of X – ray beam used, B is the full-with half maximum

(FWHM) of diffraction (in radians) and θ is the Bragg’s angle

The average crystallite size calculated is 35 nm which is in close agreement with the

TEM results.

Magnetic measurements:

The magnetic moment for iron oxide was carried out at room temperature and was observed

as 5.68 B.M. This value of magnetic moment supports the fact that the synthesized iron oxide

is in the form of Fe2O3 with actual magnetic moment 5.92 B.M. This indicates the presence

of 5 unpaired electrons in Fe2O3. Magnetic measurements were also carried out at

temperatures ranging from 300K to 100K to determine the temperature of morin transition.

The results are shown in Fig.3. 2(a) and have been reported in Table 3.2. VSM studies were

carried out at 300K to show hysteresis behavior of nanosized particles and it has been

observed that Fe2O3 show ferromagnetic behavior in nanocrystalline form. Ms value being

0.17 emu/g (Fig3.2b).


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TGA/DTA studies:

TGA/DTA transition shows an endothermic peak at 3640 C [Fig.3.3]. It simply indicates that when FeO

(OH) is heated, it takes an amount of energy and 1.5 water molecules are removed. So, TGA curve

shows that for the formation of iron oxide temperature above 3640C is required (Fig. 3.3).

Surface Area Measurement:

The BET surface area of the samples was measured by nitrogen adsorption isotherms.

Surface area of the metal oxide was 27 m2/g. Samples were activated at 473 K for 4 h prior

to the measurement.

SEM/ TEM studies

Morphology of the sample was investigated using SEM and TEM. Fig.3.4 shows typical SEM images

of the sample.TEM studies were carried out to find out exact particle size of synthesized Fe2O3. Figure

3.5 shows the TEM image of the synthesized α - Fe2O3 nanoparticles. TEM images show that Fe2O3

nanoparticles are having particle size in the range of 15nm - 49 nm [Fig. 3.5]. The size distribution

histograms for nanoparticles provided their respective sizes as 29.8 ± 8.4 nm [Fig. 3.5a], 30.6 ± 7.0 nm

[Fig. 3.5b], 26.4 ± 4.7 nm [Fig. 3.5c], 32.4 ± 6.6 nm [Fig. 3.5d], respectively.

Abstract:

α - Fe2O3 nanoparticles with rhombohedral structure are synthesized successfully by aqueous

precipitation method. From TEM study, it is found that particles are with having size of 15-49 nm.

Magnetic measurements shows that α - Fe2O3 has five unpaired electron and hence paramagnetic

in nature. XRD studies show that iron oxide was formed as α- Fe2O3 instead of the commonly

formed magnetite nanoparticles Fe3O4 or a mixture of magnetite and maghemite. This method is

advantageous over the existing methods of synthesis of nanoparticles because other methods

require specialized instrumentation, highly skilled labour, expensive materials and methods.

Therefore, the proposed precipitation method is very promising and may have extensive

applications for the synthesis of nanosized iron oxide particles.


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3.2 A simple and effective method of the synthesis of nanosized CuO particles

Transition metal oxides have many applications as catalyst [40-44] , sensors [45-48] ,

superconductors [49-50] and adsorbents [51-52]. Among transition metals oxides, copper

oxide nanoparticles are of special interest because of their efficiency as nanofluids in heat

transfer applications. It has been reported that 4% addition of CuO improves the thermal

conductivity of water by 20% [53] . CuO is a semiconducting compound with a narrow band

gap and used for photoconductive and photothermal applications [54]. Very few methods of

synthesis of copper oxide particles have been reported as compared to other oxides. CuO

particles have been synthesized using different methods like sonochemical method [55] ,

sol–gel technique [56], one-step solid state reaction method at room temperature [57],

electrochemical method [58] , thermal decomposition of precursors [59], co-implantation of

metal and oxygen ions [60] and ultrasonic spray pyrolysis [61]. A novel nano-sized copper

oxide modified carbon paste electrode has been fabricated to determine the amikacin by

cyclic voltammetry and amperometry. The oxidation current of the amikacin on nano-sized

copper oxide modified carbon paste electrode was about 40 times higher than that on bulk

CuO modified carbon paste electrode [62]. Nanosized copper ferrite spinel particles by a

precursor approach with the aid of ultrasound radiation have been synthesized [63]. Influence

of various preparation parameters on the formation of copper ferrite was studied. The

preparation parameters included concentrations of precipitating agents and copper salt,

sonochemical reaction time, calcination temperature and time. The reactions for the

formation of CuFe2O4 were explored by analyzing X-ray diffraction data obtained under

different processing conditions. Nano-powders of p-type transparent conductive copper

aluminium oxide (CAO) by co-precipitation method by adding sodium hydroxide into the

mixed solution of copper chloride and aluminium chloride have been synthesized [64]. Co-

precipitate precursors of CAO with particle size around 50-60 nm were produced after

washing, filtering, and drying of the co-precipitates, nano-powders of copper aluminium

oxide were produced when the dried co-precipitate precursors were calcined at temperature

above 1100°C. In the present work, we have synthesized CuO nanoparticles by simple

aqueous precipitation method by taking aqueous ammonia as precipitating agent. This

method involves a simple, cheap and one step process for synthesis of CuO nanaoparticles.

The obtained particles of CuO have size ranging from 12-35 nm. The synthesized

nanoparticles were characterized by XRD, TGA/DTA, Magnetic susceptibility and TEM.


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3.2.1 Results and discussions:

X-ray studies:

X-ray diffraction of synthesized oxide is shown in Figure (3.6). X-ray diffraction pattern of

pure copper oxide indicated that copper oxide is in the form of CuO Figure ( 3.6) . In X-ray

diffraction, some prominent peaks were considered and corresponding d-values (2.52028,

2.31782, 1.86566….) were compared with the standard [JCPDS file No. 05-661] (Table-3.6).

X-ray diffraction shows that metal oxide is pure CuO having monoclinic structure.

Magnetic measurements:

The magnetic moment for copper oxide is found to be 1.731 B.M. This value of magnetic

moment supports the fact that the formed copper oxide is in the form of CuO with actual

magnetic moment 1.732 B.M. This indicates that 1 unpaired electron is present in CuO (Fig.3.7).

Thus the oxide formed is paramagnetic in nature (Table 3.7).

Thermal Analysis:

Thermal analysis includes a group of techniques in which a physical property of a substance

is measured as a function of temperature or time while the substance is subjected to a

controlled temperature programme. The analysis involves thermogravity (TG), differential

thermal analysis (DTA) and derivative Thermogravimetry (DTG). Thermal Gravimetric

studies of the calcined oxides prepared were done between a temperature range of 10-10000C

under N2 atmosphere. The TGA/DTA curves of the oxide is shown in Fig.3.8. The maximum

total weight loss observed for Copper oxide and their corresponding temperature is

summarized in Table (3.8). Results showed in the synthesized oxide undergoing

decomposition, dehydration or any physical change. From TGA curve we observed that

copper oxide show stable weight loss above 959.880C. In DTA curve also, there is

exothermic and endothermic peak which shows phase transition, solid state reach on any

chemical reaction occurred during heating treatment. From TGA curve we observed that

Copper Oxide showed stable weight loss above 959.880C [Fig.3.8].

SEM/TEM studies

Morphology of the sample was investigated using SEM and TEM. Fig.3. 9 shows typical

SEM images of the sample. TEM studies were performed to find out exact particle size of

synthesized CuO. Figure (3.10) shows the TEM image of the synthesized CuO nanoparticles.

It shows that the CuO nanoparticles are having size of the obtained nanaoparticles is in the

range of 12-35 nm ( Fig. 3.9).


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Abstract:

CuO nanoparticles with monoclinic structure are synthesized successfully by aqueous

precipitation method. From TEM study, it is found that particles are monoclinic with average size

of 12-35 nm. Magnetic measurements shows that CuO has one unpaired electron and hence

paramagnetic in nature. This method is advantageous over the existing methods of synthesis of

nanoparticles because other methods require specialized instrumentation, highly skilled labour,

expensive materials and methods. Therefore, the proposed precipitation method is very promising

and may have extensive applications.


125

3.3 A simple and effective method of the synthesis of nanosized ZnO particles:

Metal oxides have attracted lots of attention over last few years due to their ability to

withstand harsh process conditions. Metal oxides such as NiO and ZnO are of particular

interest as they are regarded as safe materials for human beings and animals. The use of zinc

oxide has been seen as a viable solution for environmental protection.Recently,

Nanotechnology have emerged as the forefront of science and technologies. The intersecting

fields of study that create this domain of advancement of nanotechnology. Nanotechnology is

forecasted as the second industrial revolution in the world. The novel properties have

attracted global interst across disciplines. ZnO nanoparticles exhibit bright stable

photoluminisence in colloidal dispersion [65]. ZnO is a versatile semiconductor material [73].

Zno has band gap energy of 3.37 eV and it has very large excitation binding energy (60 meV)

at room temperature . It is wurtzite type semiconductor [66-74]. Recently ZnO has been

attracting attention because of its demand for its thermal stability , flexibility to form

different nanostructures , commercial demand for optoelectronic devices. ZnO can form

different nanostructures [75]. ZnO has wide application in surface acoustic wave devices

[76], field emission [77], gas sensors [78], ceramics [79] , solar cells [80], nanogenrators

[81] , biosensors [82], varistors [83], electrodeposition [89] , antimicrobial textiles [84] ,

catalysis , environmental protection , biotechnology, piezoelectric behaviours [85] and

ultraviolet nanolasers [86-87]. In the present work nanosized zinc oxide particleshave been

synthesized and characterized.

3.3.1 RESULTS AND DISCUSSION

X-Ray Studies:

As is well known that properties and performance of different devices depend strongly on the

surface characteristics. X-Ray diffraction of synthesized zinc oxide is shown in Fig. (3.11).

X-ray diffraction patter of pure zinc-oxide indicated that zinc oxide in the form of ZnO

having hexagonal wutrzite structure Fig. (3.11). In X-ray diffraction, some prominent peaks

were considered and corresponding d-values (2.8179, 2.6049, 2.4786……..) were compared

with standards JCPDS file No 80-0075 (Table No. 3.10). X-ray diffraction shows that metal

oxide is pure ZnO having ZnO is a single crystalline and exhibit hexagonal structure. X-ray

diffraction shows high degree of orientation. It is found that form is anisotropic that on

average crystallites may be regarded as cylinders but they are in fact right prisms whose cross

section is an irregular hexagon. Size of the crystals was also calculated using Scherrer

equation and it was observed that it support TEM studies. X-ray diffraction data indicates that


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ZnO naoparticles have hexagonal unit cell structure. Individual nanoparticles having size 21-

40 nm were found.

Magnetic Measurements:

The zinc oxide is amphoteric oxide and semiconductor at room temperature.It has excellent

piezoelectric properties. It is possible to induce room temperature ferromagnetic like behavior

in ZnO nanoparticles without doping with magnetic impurities but simply inducing an

ferromagnetic alteration of their electronic configuration.(Fig.3.12)

Thermal Analysis:

Thermal analysis includes a group of techniques in which a physical property of a substance

is measured as a function of temperature or time while the substance is subjected to a

controlled temperature programme. The analysis involves thermogravity (TG), differential

thermal analysis (DTA) and derivative Thermogravimetry (DTG). Thermal Gravimetric

studies of the calcined oxides prepared were done between a temperature range of 10-10000C

under N2 atmosphere. The TGA/DTA curves of the oxides are shown in Fig. (3.13). The

maximum total weight loss observed for zinc oxide and their corresponding temperature is

summarized in Table (3.11). Results showed that in the synthesized oxides shows some

weight loss and oxide undergoing decomposition, dehydration or any physical change. From

TGA curve we observed that zinc oxides shows stable weight loss above 959.880C. In DTA

curve also, there is exothermic and endothermic peak which shows phase transition, solid

state reach on any chemical reaction occurred during heating treatment. From TGA curve we

observed that zinc oxide showed stable weight loss above 959.880C [Fig.3.13].

SEM and TEM Studies :

Morphology of the sample was investigated using SEM and TEM. Parts of Fig.3.14 shows

typical SEM images of the sample. Scanning electron microscopy shows the hexagonal

structure of zinc oxide Fig. (3.14). SEM images demonstrate that a bulk quantity of flower

like bunches exist. Fig.5 shows TEM images of the sample. The flower like nanostructure is

observed. During the TEM sample preparation, flower like nanostructures were not destroyed

. This indicates that the formation of flower like nanostructures is not due to aggregation.

TEM is evidence for formation of hexagonal ZnO nanoparticles. TEM studies shows that

the ZnO nanoparticle are hexagonal and size of the obtained nanoparticles is in the range 21-

40 nm. [Table 3.12]


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Abstract:

In conclusion, a general and facile approach has been developed to prepare nanosized zinc

oxide from commercially available reagents by aqueous precipitation method. There is great

attention in zinc oxide nanoparticles both from the point of view of simpler , cheaper and

easy handling using aqueous precipitation method and determination of fundamental

properties. The results indicates that nanosized zinc oxide nanopricles with hexagonal

wurtzite crystal structure. From TEM studies it is found that particle has average size of 21-

40 nm. SEM studies indicate that ZnO has hexagonal structure. Magnetic measurements

showed that ferromagnetic nature.This method is advantageous over the existing methods for

synthesis of nanosized zinc oxide. Therfore the proposed method is very much promising and

have extensive applications.


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3.4 A simple and effective method of the synthesis of NiO nanoparticles

Transition metal oxides have many applications as catalyst [88], sensors [89-92],

superconductors [93-94] and adsorbents [95-96]. NiO has a variety of specialized

applications and generally applications distinguish between "chemical", which is relatively

pure material for specialty applications, and "metallurgical grade", which is mainly used for

the production of alloys. It is used in the ceramic industry to make frits, ferrites, and

porcelain glazes. The sintered oxide is used to produce nickel steel alloys. NiO was also a

component in the nickel-iron battery, also known as the Edison Battery, and is a component

in fuel cells. It is the precursor to many nickel salts, for use as specialty chemicals and

catalysts. More recently, NiO was used to make the NiCd rechargeable batteries found in

many electronic devices until the development of the environmentally superior lithium ion

battery [97]. Nickel oxide has many catalytic applications as nickel – uranium oxide catalyst

has been used for the hydrogenation of carbon dioxide to methane [98].

Potassium/calcium/nickel oxides has been observed as a good catalyst for the oxidative

coupling of methane [99]. Mixed nickel–manganese oxides with an ilmenite and spinel

structure have been investigated in order to elucidate the effect of the crystal structure type

and cation coordination on the catalytic performance in the reactions of complete oxidation

of ethyl acetate, benzene and carbon monoxide. Nickel–manganese oxides with an ilmenite-

type structure are perspective catalysts for catalytic neutralization of exhaust gases from

organic compounds [100-103]. Nickel–manganese mixed oxides NiMn2O4 spinel was used

for the partial conversion of methane [104-105]. As nickel oxide has wide applications in

industry and catalyst for reactions, an attempt has been made to synthesize nickel oxide

nanoparticles by simple aqueous precipitation using ammonia as precipitating agent. This

method involves a simple, cheap and one step process for synthesis of NiO nanaoparticles.

The obtained particles of NiO have size from 28-50nm. The synthesized nanoparticles were

characterized by XRD, TGA, magnetic susceptibility, SEM and TEM.

3.4.1 Results and discussions

X-ray studies

X-ray diffraction of synthesized nickel oxide is shown in Fig. 3.16. X-ray diffraction pattern

of pure nickel oxide indicated that nickel oxide in the form of NiO having rhombhohedral

structure. In X-ray diffraction, some prominent peaks were considered and corresponding d-

values were compared with the standard [JCPDS file No. 89-7350] (Table-3.13). X-ray

diffraction showed that metal oxide is pure NiO having rhombhohedral structure. Size of the


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crystals was also calculated using Scherrer equation and it was observed that it supports

TEM studies.

Magnetic measurements

The magnetic moment for nickel oxide is found to be 2.691 B.M. This value of magnetic

moment supported the fact that the formed nickel oxide is in the form of NiO with actual

magnetic moment 2.828 B.M. This indicated that 2 unpaired electron being present in NiO.

Thus the oxide formed is paramagnetic in nature (Table3.16).

TGA/ DTA studies

From TGA curve we observed that nickel oxides showed stable weight loss above 600ºC

[Fig.3.18]. It simply indicates that the temperature required for formation of nickel oxide

was 600ºC (Table3.15).

SEM and TEM studies

SEM and TEM studies were performed to find out the morphology and exact particle size of

synthesized NiO. TEM showed that the NiO nanoparticles having particle size in the range

of 28 – 50 nm are in good agreement of nanosized particles (Fig.3.19 and Fig. 3.20).

Abstract:

NiO nanoparticles with rhombhohedral structure were synthesized successfully by aqueous

precipitation method. From TEM study, it is found that particles have average size of 28-50

nm. Magnetic measurements showed that NiO has two unpaired electrons and hence

paramagnetic in nature. This method is advantageous over the existing methods for

synthesis of nanoparticles because other methods required specialized instrumentation,

highly skilled labour, expensive materials and methods. Therefore, the proposed

precipitation method is very much promising and may have extensive applications.


130

Table 3.1: X-ray diffraction data for iron oxide (αααα - Fe2O3)

S. No. d ( A0)

(Observed)

d ( A0)

(Reported)

I/I0 × 100 %

(Observed)

I/I0 × 100 %

(Reported)

1. 3.6806 3.6775 35.78 58.7

2. 2.6980 2.6959 100.00 100

3. 2.5155 2.5135 83.14 63.1

4. 2.2033 2.2015 24.03 3.4

5. 1.8394 1.8379 36.98 6.1

6. 1.6949 1.6936 43.26 18.0

7. 1.4852 1.4840 26.88 18.1

8. 1.4511 1.4512 26.77 9.7


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TABLE 3. 2: Observations on magnetic susceptibilities of synthesized iron oxide

Experimental Conditions:

Applied Magnetic field= 5.0 Kilo gauss

Temperature = 296K

S. N. Name of Oxide R=µ1-µ2

(e.m.u)

W=w1-w2

(gm)

µcalculated = µ1-µ µobserved (B.M.)

1 Iron Oxide 0.741x10-

2

0.01654 5.82 5.92

µcalculated = √n(n+2) and µobserved = 2.84√RTM/HW

Where

n= no. of unpaired electron.

R = Magnetic Moment in B.M.

T = absolute Temperature.

M= Molecular weight

H= Applied Magnetic Field

W = Weight of Sample.

TABLE: 3.3: Observations of weight loss for iron oxide at corresponding temperature

range

Sr.No. Maximum % loss in weight Temperature range

1 27.3% 23-500

2 0.9% 500-994


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TABLE -3. 4: Partical size of synthesized iron oxide at different scales

S.No. Scale 50nm Scale 100nm

1 15 17

2 40 34

3 20 25

4 22 26

5 34 49

6 44 35

7 25 28

8 49 49

9 15 29

10 39 21

Range 15nm to 49nm 15 nm to 49nm


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Table-3.5 Magnetic susceptibility data of iron oxide

Temperature(K)

Volt(mV)

Magnetic moment(e.m.u.)

300

5.75

0.0050

290

5.58

0.0051

280

5.38

0.0052

270

5.17

0.0054

260

4.96

0.0055

250

4.75

0.0057

240

4.54

0.0060

230

4.33

0.0062

220

4.13

0.0056

200

3.71

0.0049

180

3.29

0.0045

160

2.88

0.0043

140

2.46

0.0042

120

2.05

0.0041

100

1.63

0.0040


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Table-3.6 X-RAY diffraction data for copper oxide

S. No. d=λ / 2sinθ

(Observed)

d=λ / 2sinθ

(Reported)

I/I 0X100%

(Observed)

I/I 0X100%

(Reported)

1. 2.52028 2.519 100 100

2. 2.31782 2.314 80.46 70

3. 1.86566 1.851 17.24 15

4. 1.50415 1.492 12.76 11

5. 1.40758 1.320 11.27 10

6. 1.37337 1.311 10.43 8


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TABLE 3. 7: Observations on magnetic susceptibilities of synthesized coppper oxide

Experimental Conditions:

Applied Magnetic field= 5.0 Kilo gauss

Temperature = 296K

Sr

.N

o

Name of Oxide R=µ1-µ2 (e.m.u) W=w1-w2

(gm)

µcalculated

= µ1-µ

µobserved (B.M.)

1 Iron Oxide 0.741x10-2 0.01654 5.82 5.92

µcalculated = √n(n+2) and µobserved = 2.84√RTM/HW

Where

n= no. of unpaired electron.

R = Magnetic Moment in B.M.

T = absolute Temperature.

M= Molecular weight

H= Applied Magnetic Field

W = Weight of Sample.

TABLE: 3.8: Observations of weight loss for copper oxide at corresponding

temperature range

Sr.No. Maximum % loss in weight Temperature range

1 27.3% 23-500

2 0.9% 500-994


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TABLE -3. 9: Particle size of synthesized copper oxide at different scales

S.No. Scale 50nm Scale 100nm

1 12 15

2 16 18

3 19 20

4 35 35

5 12 14

6 35 35

7 22 24

8 34 28

9 18 30

10 29 34

Range 12 nm to 35 nm 12 nm to 35 nm


137

TABLE-3.10:- X-RAY diffraction data of zinc oxide

S.N. d=λ/2Sinθ

(Observed)

d=λ/2Sinθ

(Reported)

I/IOx100%

Observed

I/IOx100%

Reported

1 2.8179 2.8179 57.86 57.86

2 2.6049 2.6048 44.24 44.25

3 2.4786 2.4785 100 99.99

4 1.9128 1.9128 22.92 22.92

5 1.6269 1.6269 32.43 32.45

6 1.4784 1.4785 27.62 27.64

7 1.4089 1.4087 4.40 4.39

8 1.3789 1.3789 24.32 24.30

9 1.3601 1.3601 11.41 11.41

10 1.3024 1.3025 1.90 1.91

11 1.2393 1.2392 3.80 3.81

12 1.1822 1.1822 1.90 1.90


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TABLE: 3.11: Observations of weight loss for zinc oxide at corresponding temperature

range

TABLE-3.12: Partical size of synthesized zinc oxide at different scales

S.No. Scale (20nm) Scale (100nm)

1 39 38

2 36 37

3 35 35

4 21 21

5 37 37

6 38 38

7 37 36

8 26 25

9 40 39

10 40 40

Range 21nm to 40nm 21nm to 40nm

Sr.No. Maximum % loss in weight Temperature range 0C

1 16.817% 35.03-4250C

2 13.212% 691.58-959.880C


139

Table 3.13 X-RAY diffraction data for NiO

S. No. d=λ / 2sinθ

(Observed)

d=λ / 2sinθ

(Reported)

I/I 0x100%

(Observed)

I/I 0x100%

(Reported)

1. 2.39 2.41 56 57

2. 2.07 2.08 100 100

3. 1.47 1.47 38 27

4. 1.25 1.25 13 10

5. 1.20 1.20 8 8


140

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

-4000 -2000 0 2000 4000

Fig.3.1- XRD spectra of synthesized iron oxide

Fig.3.2. (a) Morin transition curve for synthesized iron oxide nanoparticles.

(b) VSM studies of synthesized iron oxide.

100 150 200 250 300

0.8

0.9

1.0

1.1

1.2

1.3

Ferromagnetic

χχχχ vs T graph for α α α α - Fe2O

3

enter text here

Antiferromagnetic

230 Κ230 Κ230 Κ230 Κ

χχ χχ

T

Position [°2Theta] (Copper (Cu)) 20 30 40 50 60 70 80 90

0

200

400

600

800

(b)

(a)


141

Fig.3.3. TGA/DTA curve of iron oxide heated at 70o C


142

Figure 3.4 : SEM images of iron oxide partic


143

(a) (b)


144

Figure 3.5: TEM images of iron oxide particles

(c) (d)

CCHHAAPPTTEERR33 SSYYNNTTHH

Figure 3.7: VSM images of copper oxide particles

Fig.3.6- XRD spectra of synthesized copper oxide

10 200

1000

2000

HHEESSIISS AANNDD CCHHAARRAACCTTEERRIISSAATTIIOONN OOFF NNAANNOOSSIIZZEEDD MMEETTAALL OOXXIIDDEESS ((RREE

145

Figure 3.7: VSM images of copper oxide particles

XRD spectra of synthesized copper oxide

Position [°2Theta] (Copper (Cu)) 20 30 40 50 60

EESSUULLTTSS AANNDD DDIISSCCUUSSSSIIOONN))

70


146

Figure 3.8: TGA-DTA images of copper oxide particles

Figure 3.9: SEM images of copper oxide particles


147

Figure 3.10: TEM images of copper oxide particles


148

Fig. 3.11: X-ray diffraction patterns of calcined zinc oxide

Fig.3.12 Manetic measurements of synthesized ZnO


149

Fig: 3.13: TGA-DTA graph of zinc oxide.


150

Fig.3.14 (a) SEM Micrographs of zinc oxide


151

Fig. 3.15: TEM micrograph of zinc oxide under high magnification (Scale bar is 20

nanometer


152

Figure 3.16. XRD spectra of synthesized nickel oxide

Fig.3.17 Manetic measurements of synthesized ZnO

Position [°2Theta] (Copper (Cu))

10 20 30 40 50 60 70

0

2000

4000

6000

CCHHAAPPTTEERR33 SSYYNNTTHH

Figure 3.18. TGA/DTA curve of nickel oxide heated at 70

Figure 3.19. SEM

HHEESSIISS AANNDD CCHHAARRAACCTTEERRIISSAATTIIOONN OOFF NNAANNOOSSIIZZEEDD MMEETTAALL OOXXIIDDEESS ((RREE

153

. TGA/DTA curve of nickel oxide heated at 70

Figure 3.19. SEM micrographs of nickel Oxide particles

EESSUULLTTSS AANNDD DDIISSCCUUSSSSIIOONN))

. TGA/DTA curve of nickel oxide heated at 70o C

particles


154

Figure 3.20. TEM micrographs of nickel oxide particles


155

References:

1. J. Z. Xu, J. J., Zhu, H. Wang and H. Y.Chen, Anal. Lett. 36 ( 2003) 2723-2733.

2. W.zhong, B. Liu, Zhong-kuan, Ren, Xiang-zhong and Zhang, Jr. of Alloys and

Compounds., 465 ( 2008) 261-264.

3. L. H.Chun, J.L. Lu, C.L. Chu, C.Y. Lai, G. Wu, 2nd international conference 2008 2nd

IEEE International Nanoelectronics Conference, 485-488.

4. T. G. Altincekic, I. Boz, S. J. Aktürk , Nanoscience Nanotechnology. 8 (2008)874-877.

5. S.Bennici,V. Gervasini, A. Ragaini , Ultrasonic sonochemistry, 10, 2(2003) 61-64.

6. M.Yang, J. Hu, X.Yan, C.Cheng, Z.Zhao, Y.Zuo, Surface and interface Physics papers A,

155, 2(2011) 692-698.

7. H.Wei, H. Sun, S. Wang, G. Chen, Y. Hou, H. Guo, X. Ma, Jr. of Natural Gas Chemistry,1

(2010) 393-396.

8. A.Guimin, Z. Yang, L.Zhimin, Zhenhang, H.Buxing, M. Shidding, L.Jianping, Nanotechnology,

19 ( 2008) 101-103.

9. S.S.Sharma.,K.Nomura, Y.U.Jihira, , Journal of Material Science, 26 (1999) 4104-4109.

10. V.Pillai, P. Kumar, M.J. Hou, P. Ayyub, D.O. Shah, Advance in colloid and Interface

Science, 55 (1995)241-269.

11. W. Rongcheng, Q. Jiuhui, H. Hong, Y. Yunbo , Journal of Beijing University of chemical

technology (Natural science edition), 48 (2003) 2311-2316.

12. W. R. Zou, Z. Han, J. S. Zhang, L.Hangmin, Jr. of Chemical and Engineering data, 51 (

2006) 534-541.


156

13. H. Runping, H.Lina, Z. Xin, X. Yanfang, X. Feng, L. Yinli, Y.Wang, Jr. of Chemical

Engineering, 149 (2009) 123-131.

14. P.Baldrin,V. Merhautova, J. Gabriel, F.Nerud, P.Stopka, M.Hruby, M.J. Benes, Applied

Catalysis B-Environmental, 66 ( 2006) 258-264.

15. N.S.Chaubal, M.R. Sawant, catalysis communications, 7 (2006)443 - 449.

16. L.Sanchez, J.A. David, Applied Catalysis A, 291 (2005) 230 - 237.

17. T. Zaki, Journal of Colloid and Interface Science, 284 (2005) 606 - 613.

18. E.Rombi, I.Ferino, R.C. Picciau, V. Solinas, R.Buzzoni, , Applied Catalysis A, 266 (2004)

73 - 79.

19. R.Andreozzi, C.Vincenzo, M.Raffaele , Water Research, 37 (2003) 3682 - 3688.

20. S.H.Taylor, G. Hutchings, J.M. Palacios,L. Lee, Catalysis Today, 81 (2003) 171 - 178.

21. B.Sreedhar, V. Bhaskar, T. Sridhar, L. Srinivas, K. S.Klára, Journal of Molecular Catalysis

A: Chemical ,191( 2003) 141 – 147.

22. G. Ketteler, W.Ranke, R.Schlogl, Journal of Catalysis, 212 ( 2002)104 – 111.

23. J.Bandara, A. Mielczarski, A. Lopez, I.Kiwi, Applied Catalysis B: Environmental 12 (2001)

321- 333,

24. S. Sugiyama, K. Kastuma, N. Fukuda, T.Shono, T. Moriga, H. Hayashi, Catalysis

Communications, 2 ( 2001) 285 – 290.

25. H.Grabowska, R. Klimkiewicz, J. Wrzyszcz, L.Syper, Journal of Molecular Catalysis A:

Chemical 154 (2000)225 - 228.


157

26. V.Duma, D. Honicke, Journal of Catalysis, 191( 2000)93-104.

27. V.Dumaa, K. Poppa, M.C.Kung, H.Zhoub,S.Nguyenb, S. Ohyamac, H.H. Kung, C.L.

Marshall, Chemical Engineering Journal, 99 (2004) 227 - 236.

28. C.T.Wang, R.J.Willey, Catalysis Today, 52 ( 1999) 83 - 89.

29. S.Chou, H. Chihpin, Chemosphere, 38 (1999) 2719.

30. Y.Wang, B.H. Davis, Applied Catalysis A, 180 (1999) 277 -288.

31. M.Lauwiner, R. Roth, P. Rys, Applied Catalysis A, 177 (1999)9 -14.

32. M.Benz, M. V. Kraan, A.M. Prins, Applied Catalysis A: General 172 (1998) 149 - 155.

33. P.Baldrian, M. Vera, J. Gabriel, F.Nerud, P. Stopka, H. Martin ,M.J. Benes, M. Applied

Catalysis B: Environmental, 66 (2006) 258 - 264.

34. N.S.Chaubal, M.R. Sawant, Catalysis Communications, 7 (2006)443 - 449.

35. S.L.Miller, L.E.Orgel, Englewood Clifts, N.J., P.83 (1974)129- 134

36. P. Horowitz, J. Berger and A.Katchalsky, Nature, 228 (1970) 636 – 639.

37. J.Wang, J., Zhu, Z.Munir, .Talanta, 84 (2011) 783-788.

38. J.Chomoucka, J. Drbohlavova, D.,Huska, V. Adam, R. Kizek, R. Hubalek, Pharmacological

Research, , 62 (2010) 144-149.

39. C.S.Kumar, F.Mohammad, Advanced Drug Delivery Reviews, 63 (2011) 789-808.

40. J.Z.Xu J.J. Zhu, H. Wang and H.Y.Chen, Anal. Lett. 36 (2003) 2723-2733.

W.zhong B. Liu, , Z.kuan, R. X.zhong Jr. of Alloys and Compounds. 465 (2008)261-264.


158

41. H.C. Lu; J.L. Lu; C.L. Chu; C.Y. Lai; G. Wu, 2nd international conference 2008 2nd

IEEE International Nanoelectronics Conference, 485-488.

42. T.G.Altinçekiç I.Boz , S. Aktürk , Nanosci Nanotechnol., 8 ( 2008)874-877.

43. B.Simona , A. Gervasini and V. Ragaini , Ultrasonic sonochemistry, 10 (2003)61-64.

44. M.Yang, J.He,H. Xiaochun, C. Yan, Z.Cheng,and Y. Zhao, Nanosci Nanotechnol., 8( 2008)874-877.

45. H. Zuo, Surface and interface Physics papers A 155( 2011)692-698.

46. H. Wei, H. Sun, S. Wang, G. Chen, Y.Hou, H. Guo1,

X. Ma1,Jr. of Natural Gas Chemistry,1 (2010) 393-396.

47. A.Guimin, Z.Yang, L.Zhimin, M.Zhenhang., H. Buxing., M. Shidding and L. Jianping,

Nanotechnology, 19 (2008)101-103

48. Sharma., S.S. Nomura, K. and Jihira,Journal of Material Science, 26

(1999) 4104-4109.

49. V.Pillai, P. Kumar, M.J. Hou, P. Ayyub, D.O. Shah, Advance in colloid and Interface

Science, 55 (1995) 241-269.

50. W.Rongcheng, J.Qu, H.He and Y. Yu, Journal of Beijing University of chemical technology

(Natural science edition), 48 (2003) 2311-2316.

51. W.R.Zou, Z. Han, J. Zhang, J. Shi and Hangmin, Jr. of Chemical and Engineering data, 51 (

2006)534-541.

52. H.Runping, H. Lina, Z. Xin, Z. Yanfang, X. Feng, X. Yinli, L. and Y.Wang,

Jr. of Chemical Engineering, 149 (2009), 123-131.

53. S.Lee, U.S. Choi, S. Li, J.A. Eastman, J. Heat Transfer, 121(1999), 280.

54. A.Rakhshni, Preparation, Solid State Electron., 29(1986) 7 -17.

55. R.V.Kumar,Y. Diamant, Y. Gedanken, Chem. Mater. 12(2000) 2301-2305.

56. K.Borgohain,K. Singh, J.B. Rama Rao, M.V., Shripathi, T. Mahamuni, S. Phys. Rev., 61

(2000), 11093.

57. J.Xu, J.F. Ji, W. Shen, Z.X. . Tang, S.H. Ye, X.R. Jia, D.Z. Xin, X.Q., Solid State Chem., 147

( 2000) 516.


159

58. K.Nakao, S. Ikeyama, M. Mizota, T. Jin, P. Tazawa, M. Miyagawa, Y. Miyagawa, S. Wang,

S. Wang, Rep. Res. Cent. Ion Beam Technol., 18( 2000 ) 153.

59. A. Punnoose, A. Magnone, H. and S. M. S. Bonevich , Phys. Rev. B 64, 64 (2001)174-

420.

60. W.zhong , B. Liu, Z.K. Luo, X.Z. Ren and P.X. Zhang, Jr. of Alloys and Compounds,1-

2(2008),261-264.

61. L.Yu , REU Research Accomplishments,1( 2008)46 – 47.

62. J.Z. Xu, J.J.Zhu, H. Wang & H.Y. Chen , Analytical Letters Volume 36, Issue 13(2003)2723-

2733.

63. W.zhong , B. Liu, Z.K. Luo, X.Z. Ren, P.X.Zhang, sonochemical methods, 465, 1–2(2008)

261–264.

64. H.S.Lu,J.Lu,C.L.Chu,C.Y.Lai,G.W.Wu,research.cgu.edu.tw/ezfiles/14/1014/img/651/97-B-

32.pdf

65. H.M Xiong ,D.G.Shchukin , H.Mohwald, Y.Xu andY.Y.Xia, Angewandte Chemie

International Edition, 15 (2009) 2727-2731

66. D.C.Look , Mater.Sci.Eng.B 80 (2001) 383

67. C.M. Lieber , Solid State Communication ,66 (1998) 5309

68. Y.Zhang , K.Suenaga, C. Collies, S.Iijima , Science 281 (1998) 973

69. L.Vayssieres, K.Kies ,A.Hagfeldt, S.E.Lindquist, Chem. Mater, 13 (2001) 4395

70. Z.W.Pan , Z.R.Dai, Z.L.Wang, Science 292 (2001) 1947

71. W.C.Schin, M.S. Wu, J.Cryst. Growth 137 (1994) 319

72. C.X.Xu, X.W.Sun , Appl. Phys. Lett. 83 (2003) 3806

73. R.Paneva, D.Gotchev,Sens.Actuat.A :Phys.72 (1999) 79

74. L.Gao,Q.Li, W.L.Luan, J.Am. Ceram.Soc. 85 (2002) 1016

75. N.F.Cooray, K.Kushiya, A.Fujimaki, D.Okumura,M.Sato, M.Ooshita, O.Yamase,Jpn.J.Appl.

Phys. 38 (1999) 6213


160

76. P.X.Gao, Y.Ding ,W.Mai, W.L.Huges, C.S.Lao, Z.L.Wang, Science 309 (2005) 1700

77. E.Topoglidis, A.E.G.Cass, B.Oregan, J.R.Durrant, J.Electoanal. Chem. 517 (2001) 20

78. N.T.Hung, N.D.Quang, S.Bernick, J.Mater. Res. 16 (2001) 2817

79. J.A.Rodriguez, T.Jirsak, J.Dvorak,S.Sambasivan, D.J.Fisher, J.Phys. Chem. B 104 (2000)

319

80. A.B.Moghaddam, T.Nazari,J.Badraghi and M.Kazemzad ,Int.J. Electochem. Sci. , 4 (2009)

247-257

81. R.Rajendran, C.Balakumar, H.A.M. Ahammed , S.Jayakumar, K.Vaideki and E.M.Rajesh,

Int. J. of Engineering Science and Technology , 1 (2010) 202-208

82. Z.L. Wang and J.Song ,”Piezoelectric naogenerators based on zinc oxide nanowire arrays,”

Science ,312 (2006) 242-246

83. X.Wang ,J.Song,J.Liu and L.W.Zhong, “Direct-Current nanogenerator driven by ultrasonic

waves,” Science , 316 (2007) 102-105

84. C.Chang, V.H.Tran ,J.Wang, Y.K.Fuh and L.Lin ,”Direct write piezoelectric polymeric

nanogenerator with high energy conversion efficiency,” Nanoletters , 2 (2010) 726-731

85. S.Xu, Y.Quin, C.Xu,Y.Wei,R.Yang and Z.L. Wang ,”Self powered nanowire devices” Nature

Nanotechnology,5, 5 (2010) 366-373

86. H.M.Huang,S.Mao, H.Fecik, H.Yan, Y.Wu,H.Kind,E.Weber,R.Russo, P.D.Yang, Science

292 (2001) 1897

87. J. Xu , J.Zhu, J. Wang and H.Chen, Anal. Lett. 36,13(2003): 2723-2733.

88. W.Lv, L.Bo, L.Zhong , X.zhong and Z. P.Xin ,Jr. of Alloys and Compounds. 465(2008) 261-

264.

89. H.C. Lu, J.L. Lu, C.L. Chu, C.Y. Lai, G. Wu, 2nd international conference, 2nd IEEE

International Nanoelectronics Conference :1 (2008) 485-488.

90. C.Altinçeki, Boz , S.Aktürk , Nanosci Nanotechnol, 8 (2008): 874-877.

91. B.Simona , G.Antonella and R.Vittorio, Ultrasonic sonochemistry 10(2003) 61-64.


161

92. Y.Mingqing , H.Junhui ,H. Xiaochun , Y.Chunxiao , Z. Cheng, Y.Zhao and G. Surface and

interface Physics papers A 155 (2011), 692-698.

93. W.Hongbing , S.Hongwen ,W. Sumei, C. G. Chen, Y. Hou, H. Guo, X. Ma , Jr. of Natural

Gas Chemistry, 3 (2010), 393-396.

94. A. Guimin, Z. Yang, L.Zhimin, M.Zhenhang., H. Buxing., M. Shidding and L. Jianping

Nanotechnology, 19 (2008) 101-103.

95. S.Sharma., S.S. Nomura, K. and Jihira ,Journal of Material Science, 26 (1999), 4104-4109.

96. V.Pillai, V. Kumar, P. Hou, M.J. Ayyub, P. Shah, Advance in colloid and Interface Science,

55 (1995) 241-269.

97. R. Wu, J. Qu, H. and Y. Journal of Beijing University of chemical technology (Natural

science edition), 48 (2003)2311-2316.

98. A.Zou, W R. Han, Z.Zhang, J. Shi and Hangmin, Jr. of Chemical and Engineering data, 51

(2006) 534-541.

99. H.Runping, H. Lina, Z. Xin, Z. Yanfang, X. Feng, X. Yinli, L. Wang,Jr. of Chemical

Engineering, 149 (2009)123-131.

100. Handbook of Inorganic Chemicals", Pradniak, Pradyot; McGraw-Hill Publications, 2002.

101. J.Frank and A. Murray,Applied Catalysis A: General, 100 (1993) 131-143.

102. K. M. Dooley, J.R.H. Ross, Applied Catalysis A: General, 90 (1992) 159-174.

103. R.M. María ,P. Bibiana, P. Barbero and L E. Cadús ,Applied Catalysis B:

Environmental,1–2 (2007) 1-10

104. R.C.Comptes R. C., Maha H.,S. Ouaguenouni, B. A. Kiennemann,A. Barama, ,Applied

Catalysis B: Environmental,12 (2009) 740-747


162

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