encyclopedia of energy research and policy

ENCYCLOPEDIA OF ENERGY
RESEARCH AND POLICY

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ENCYCLOPEDIA OF ENERGY
RESEARCH AND POLICY

A. L. ZENFORA
EDITOR

Nova Science Publishers, Inc.
New York


Copyright © 2010 by Nova Science Publishers, Inc.
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Published by Nova Science Publishers, Inc. 

New York


CONTENTS
Preface

xi

Research and Review Studies

1

Chapter 1

Energy Markets
United States Government Accountability Office

3

Chapter 2

Three-Dimensional Simulation of Base Carrier Transport Effects in
Back Side Point Contact Silicon Solar Cells
K. Kotsovos and K. Misiakos

53

Multiple Effect Distillation of Seawater Water Using Solar Energy
– The Case of Abu Dhabi Solar Desalination Plant
Ali M. El-Nashar

85

Solid State Organic Photoelectrochemical Solar Energy Conversion
Based on Conjugated Substituted Polythiophenes

Teketel Yohannes

159

Chapter 3

Chapter 4

Chapter 5

A New Approach to Hybrid Systems of Renewable Energy
Utilization
Yu.V. Vorobiev, J. Gonzalez-Hernandez,
P. Gorley, P. Horley and L. Bulat

201

Chapter 6

Dye-Sensitized Nano SnO2:TiO2 Solar Cells
Weon-Pil Tai

Chapter 7

Strategies for Reducing Carbon Dioxide Emissions - The Case of
Botswana Rural Communities
C. Ketlogetswe and T.H. Mothudi

231

The Applying of Coatings and Surface Thermal Treatment of
Materials in Solar Furnaces: Theory and Experiments
V.V. Pasichny and B.A. Uryukov

245

Chapter 8

219


vi
Chapter 9

Chapter 10

Contents
Transparent Conductive Layers of Tin, Indium, and Cadmium
Oxides for Solar Cells
Yu.V. Vorobiev, J. Gonzalez-Hernandez, P. Gorley,
V. Khomyak, S. Bilichuk, V. Grechko and P. Horley
Dynamic Impedance Characterization of Solar Cells and PV
Modules Based on Frequency and Time Domain Analyses
D. Chenvidhya, K. Kirtikara and C. Jivacate

Chapter 11

Wind Energy Technology Overview
United States Department of the Interior, Bureau of Land
Management

Chapter 12

Federal and State Regulatory Requirements Potentially Applicable
to Wind Energy Projects
United States Department of the Interior, Bureau of Land
Management

277

301
327

367

Chapter 13

Commercial Wind Energy Projects
United States Department of the Interior, Bureau of Land
Management

Chapter 14

Biomass And Bioenergy Research In Tropical Africa: State Of The
Art, Challenges And Future Directions
Jonathan C. Onyekwelu and Shadrach O. Akindele

385

Poplar Biomass of Short Rotation Plantations as Renewable Energy

Raw Material
Bojana Klasnja, Sasa Orlovic, Zoran Galic and Milan Drekic

419

Biobased Polymers by Chemical Valorization of Biomass
Components
B. Kamm, M. Kamm, I. Scherze, G. Muschiolik and U. Bindrich

449

Experimental Analysis of Small Combustion Thermal Systems
Based on Pellets
J.C. Morán, J.L. Míguez, E. Granada and J. Porteiro

481

Chapter 15

Chapter 16

Chapter 17

Chapter 18

Chapter 19

Chapter 20

Negative Emission Biomass Technologies in an Uncertain

Climate Future
Kenneth Möllersten, Zuzana Chladná,
Miroslav Chladný and Michael Obersteiner
A Review of the Socio-Economic and Environmental Benefits of
Biomass Gasification Based Power Plant: Lessons from India
Kakali Mukhopadhyay
The Energy Balance and Fuel Properties of Biodiesel
Mustafa Acaroglu and Mahmut Ünaldı

377

501

549
589


Contents
Chapter 21

An Experimental Study on Performance and Exhaust Emissions of a
Diesel Engine Fuelled with Various Biodiesels
Nazim Usta

Chapter 22

New Materials from Lignin
Carlo Bonini and Maurizio D’Auria

Chapter 23

Offgas Recycle for Increased Heat Production from Aerobic
Thermophilic Treatment of Swine Waste: Pilot Studies and FullScale Design
James W. Blackburn, Zhe Wang and Mahesh Mudragaddam

Chapter 24

Nuclear Dynamics Modelling by Recurrent Neural Networks
F. Cadini, E. Zio and N. Pedroni 675

Chapter 25

Primary Cosmic Ray Studies Based on Atmospheric Cherenkov
Light Technique at High-Mountain Altitude
A.L. Mishev, S. Cht. Mavrodiev and J.N. Stamenov

Chapter 26

Development of Subchannel Analysis Code for CANDU-SCWR
Yu Jiyang, Wang Songtao, Jia Baoshan

Chapter 27

Application of Best Estimate Computational Tools for Safety
Accident Analysis in Nuclear Plants
Anis Bousbia Salah, Tewfik Hamidouche and Francesco D’Auria

vii

603

625

653
675

731
779

811

Chapter 28

Advanced Fuel Fusion Reactors: Towards a Zero-waste Option
Massimo Zucchetti

829

Chapter 29

Solar Thermal Power Generation on Mars
Viorel Badescu

843

Chapter 30

Equilibrium Phases in Zirconium Alloys of Concern to the Nuclear
Industry: Isothermal Sections of the Zr-Cr-Sn and Zr-Cr-Ti Systems
S.F. Aricó, R.O. González and L.M. Gribaudo

893

Nuclear Nonproliferation: IAEA Safeguards and Other Measures to
Halt the Spread of Nuclear Weapons and Material
Gene Aloise

915

Radial-Bias-Combustion and Central-Fuel-Rich Swirl Pulverized
Coal Burners for Wall-Fired Boilers
Zhengqi Li

939

Chapter 31

Chapter 32

Chapter 33

Chapter 34

Fuel Cell Combined Cycle Power Generation System Installed into
Micro-Grid
Shin’ya Obara

1061

Electricity from Renewable Energy Sources: A Multi-Criteria
Evaluation Framework of Technologies

Fausto Cavallaro

1107


viii

Contents

Chapter 35

Gas Turbines and Electric Distribution System
Francisco Jurado

1139

Chapter 36

Micro CCHP: Future Residential Energy Center
R. Z. Wang and D. W. Wu

1173

Chapter 37

Sensitivity Calculation in Real Time Transmission Network and
Energy Markets
Jizhong Zhu

1199

Wide-Area Monitoring and Analysis of Inter-Area Oscillations
Using the Hilbert-Huang Transform
A. R. Messina, M. A. Andrade and E. Barocio

1219

Chapter 38

Chapter 39

Unconventional Problems in Power Systems Protection
Mahmoud Gilany and Mohamed A. Mahmoud

Chapter 40

BME-Generated Temperature Maps of the Nea Kessani Geothermal
Field
Konstantinos Modis, Hwa-Lung Yu, George Christakos,
Robert Stewart and George Papantonopoulos

Chapter 41

Chapter 42

Chapter 43

Chapter 44

Chapter 45

1251

1265

Advances in Studies of Thermal-Fluid Geochemistry and
Hydrothermal Resources in China
Jianguo Du, Youlian Zhang and Heping Li

1281

A Comparative Analysis of the Geothermal Fields of Larderello and
MT Amiata, Italy
Giovanni Gianelli

1321

Sedimentary Characteristics of Coal Beds in Intramontane Basins
(Massif Central, France)
Wang Hua and Xiao Jun

1349

Coupling of Thermal and Chemical Simulations in a 3-D Integrated
Magma Chamber-Reservoir Model: A New Geothermal Energy
Research Frontier
Surendra P. Verma and Jorge Andaverde
Determination of the Damage Effect in Geothermal Wells Using
Inflow Type Curves
A. A. Aragón, S. L. Moya and A. M. C. Suárez

1361

1403

Expert Commentaries

1443

Commentary A Innovative Techniques for the Simulation and Control of Nuclear
Power Plants
Antonio Cammi and Lelio Luzzi

1445


Contents

ix

Commentary B Analysis and Characterization of Complex Inter-Area Oscillations
from Measured Data: A Time-Frequency Perspective
A. R. Messina, E. Barocio and M. A. Andrade

1449

Index

1453

PREFACE
Chapter 1 - To better understand how changes in domestic and international petroleum
products markets have affected prices, this book evaluates trends in (1) the international trade
of petroleum products, (2) refining capacity and intensity of refining capacity use
internationally and in the United States, (3) international and domestic crude oil and
petroleum product inventories, and (4) domestic petroleum supply infrastructure. This is an
excerpted and indexed version.
Chapter 2 – This work presents a theoretical investigation of rear junction point contact
silicon solar cells through three-dimensional numerical simulation based on the solution of
minority and majority carrier transport equations in the base of the cell. The device series
resistance is evaluated through the simulated current-voltage (IV) curves under AM1.5
illumination conditions and its dependence on back contact geometry is examined. Results are
presented which show the influence of the majority carrier transport in the base to the solar
cell performance. A comparison is also performed with two other similar types of point
contact solar cells, one with the emitter located on the front surface and the other on both
surfaces, as well as with a conventional solar cell structure.
Chapter 3 - This report describes the solar desalination test plant in Abu Dhabi, UAE and
gives a summary of its first year performance and economics. The plant has been operating
successfully for 18 years supplying fresh water to the City of Abu Dhabi. The plant was
commissioned in September 1984 and was running until the year 2002 when it was
dismantled after fulfilling its objectives. The aim of the plant is to investigate the technical
and economic feasibility of using solar desalination of seawater in providing fresh water to
remote communities in the Middle East and to obtain long-term performance and reliability
data on the operation of the plant. The plant has proved its technical feasibility and proved to
be reliable in operation with few minor maintenance problems that required slight plant
modification. Maintenance routines were established to maintain high plant performance. The
economic feasibility of the plant was established by comparing the cost of water from a solar
MED plant with a conventional MED plant using fossil fuel for plant capacity ranging from

100 m3/day to 1000 m3/day. It was found that the cost of water from solar MED plants is
competitive with that from a conventional MED plant if the cost fuel continues to rise.
Chapter 4 - The utilization of organic materials for photovoltaic devices has been
investigated intensely during the last couple of decades. Earlier studies concentrated on
molecules that had high optical absorption in the visible region of the electromagnetic
spectrum. Recent discovery of conjugated polymers having semiconductor-like behavior has


xii

A. L. Zenfora

started to stir excitement because such materials are not only able to function in a similar
manner to the inorganic semiconductors but also have important advantages such as: low cost,
light weight, ease of fabrication and the possibility of large area coatings. Their use as
photoactive electrodes is of increasing interest, as the processing possibilities of conjugated
polymer materials have become more developed. Furthermore, the high absorption
coefficients of these materials and the possibility of varying the band gap by molecular
engineering have opened up new options for solar energy conversion.
Among the conjugated conducting polymers, neutral, substituted polythiophenes exhibit
interesting properties as semiconducting photoactive materials and are used for conversion of
optical energy into electrical energy.
Investigation of the photoelectrochemistry of conducting polymers was mainly focused
on their use as protective films against photocorrosion and as photoactive electrodes in liquid
junction photoelectrochemical cells (PECs). Photocorrosion and side reactions involving the
electrolyte solution and the difficulty of packaging limit the working life of liquid electrolyte
PECs. Solid-state PECs with the use of solid polymer electrolytes provide a means to
eliminate this problem since they can easily be processed into thin films over large areas and
are easier to encapsulate. The solvent-free ion conducting polymer electrolytes eliminated
handling, portability, and packaging problems encountered in liquid junction

photoelectrochemical cells. Basically, the photoelectrochemical properties occurring in these
systems are the same as those occurring in systems based on semiconductor photoelectrodes
in contact with liquid electrolytes.
In this chapter an overview of the studies made on solid-state photoelectrochemical solar
energy conversion devices using standard photoelectrochemical and photoelectrical
characterization techniques is presented. The photoelectrochemical cells contain a thin film of
semiconducting conjugated substituted polythiophenes as a light-harvesting unit, a redox
couple complexed with an ion conducting polymer electrolyte, and a counter electrode.
Chapter 5 - A general analysis is given of hybrid systems consisting of different
combinations of 4 devices frequently employed for renewable energy utilization: Photovoltaic
Solar Panel (PV), Solar Thermal Plane Collector (ST), Wind Generator (WG) and Heat-toElectric/Mechanic Energy Convertor (HE); some of the combinations include radiation
energy flux concentrators of different degrees. The main result of the consideration made is
that the hybrid systems are more efficient than the sum of the constituents and more stable in
relation to spontaneous variations of the renewable energy source potential (like wind
velocity, insolation, etc.). However, to realize the possibilities mentioned, all the elements of
a given hybrid system have to be especially designed and made for this specific system. For
example, the PV panel for the hybrid PV/Thermal system ought to have a substrate with high
thermal conductivity, to allow for heat extraction from the panel by the adjacent Solar
Thermal Plane Collector, and practically no commercial panels with these characteristics are
available. Besides, the PV panel as a part of the hybrid system will demand a special choice
of semiconductor material and surface treatment which could be different from those for
conventional panels. The limiting efficencies for some hybrid systems are estimated; these
efficiencies exceed the efficiencies of separate use of the devices discussed. The most
promising hybrid system is the PV panel made as spectrum splitter in combination with HE
converter, of which total efficency could be around 50 %.
Chapter 6 – The nanostructured SnO2:TiO2 bilayered and composite solar cells
sensitized by eosin Y and RuL2(NCS)2 dyes are prepared and the photoelectrochemical


Preface

xiii

properties of the cells are investigated. The semiconductor films possess the grain size of
nanometer order and have nanoporous structure. The bilayered cell shows higher IPCE
(incident photon- to-current conversion efficiency) value than the single and composite cells.
A maximum IPCE value of 88.1% was reached at 540 nm wavelength in the bilayered cell
with 3.5μm-thick SnO2 and 7μm-thick TiO2 sensitized by RuL2(NCS)2 dye. The higher
IPCE value in the bilayered cell is attributed to the promotion of the charge separation by fast
electron transfer process from the excited dye to SnO2 in the SnO2/TiO2/dye system with
different conduction band edge energy positions.
Chapter 7 - The International Community’s pre-occupation with the ever-escalating
dangers posed by gaseous pollutants need not be overemphasized. Suffice to mention,
however that the magnitude of the dire negativity of pollutants is reflected in the numerous
international charters that were promulgated with a common objective to sensitise the world
about the need to move toward setting up minimum permissible levels of emission for
activities whose execution result in atmospheric pollution. In addition, authorities have also
gone so far as to offer incentives / motivation as a means of assuaging nations towards
implementing various strategies for minimising atmospheric pollutions. This paper explicates
efforts taken by. The government of Botswana in an effort to strive for compliance with
international protocols and standards to safeguard against deterioration of the planet. Focus
will specifically be paid to examining any concrete measures taken with the view to curb the
negative impacts of carbon dioxide gas. The suitability and sustenance or, otherwise, of
government projects envisaged for reducing carbon dioxide emission levels generated during
the combustion of fuelwood and other related energy sources used by rural communities in
Botswana will also be discussed.
Chapter 8 - Solar furnaces make it possible to obtain a temperature of heating equivalent
to 3500 K and above it an oxidizing air medium and without any outside contamination. They
are used for investigation of materials in the Institute for Problems of Materials Science
(IPMS) of theNational Academy of Science of Ukraine (NASU) for the past 40 years. The

created experimental base consists of 14 different solar installations of power from 0.1 up to
10 kW. They are included in the two laboratories located in Kyiv and on the Black Sea coast.
Some optical furnaces on Xe arc lamps which are the simulators of solar furnaces are added
to the experimental base. In the given chapter the works of the last few years are
concentrated. They are dedicated to surface heating of materials intended for obtaining
coatings and improving their protective, decorative and other operational characteristics. The
specialists of various fields of engineering and production are engaged in the development of
these energy-intensive processes with the use of traditional energy sources. Their substitution
for renewable solar radiation if it is possible can cause not only saving on utilities saving but
in some cases the improvement of coatings quality due to chemical purity of the heating
source. Some theoretical and experimental results of the investigation in the given field
fulfilled in the IPMS are represented in the proposed work. Using an approximate integral
method for solving heat conduction equation the problem is solved for the determination of
the rate of thermal treatment of a surface by partial melting in a solar furnace when the
sample is stationary and moves relative to the focal spot depending upon the given thickness
of fused layer. Taking into account the absence hitherto of industrial (commercial) production
of solar furnaces the theoretical and practical foundations have been developed in the IPMS
for the creation of solar radiation concentrators on the basis of metallic antennae with plane
mirror facets. As it is described in the given work the energy characteristics of these


xiv

A. L. Zenfora

concentrators fully come up to the standards which are necessary for the realization of the
greatest part of the investigated processes.
Chapter 9 - Transparent conductive oxides SnO2, In2O3-SnO2 (ITO) and CdO are
widely used for different optoelectronic devices, including photovoltaic applications.
Depending on technological conditions, oxide films can be either high- or low-resistive. This

paper presents the results of complex investigation of technological parameters influence
(such as chamber pressure, substrate temperature, magnetron cathode power, and duration of
isothermal annealing in the air) on specific resistance and transmission coefficient of oxide
thin films, grown by reactive magnetron sputtering. Ar-O2 mixture was used as a carrier gas
for direct current sputtering; high-frequency sputtering was performed in pure Ar atmosphere.
Substrates for the films were made of quartz glass and silicon. Significant attention was paid
to the transformation of defect subsystems after isothermal annealing in the air. The authors
determined optimal technological regimes allowing to obtain reproducible high-quality thin
films of tin, indium and cadmium oxides with the following electrical and optical parameters:
SnO2 – specific resistivity ρ = 6 – 15.10-4 Ω⋅cm, optical transmission T = 90 – 95% in
transparency region; ITO – ρ = 4 – 6.10-4 Ω⋅cm, T = 90 – 95%; CdO – ρ = 5 – 20.10-4 Ω⋅cm,
T = 80 – 90%.
Chapter 10 - This article describes new methods to derive dynamic impedance of solar
cells and PV modules from time and frequency domain analyses. Initially, the authors
propose a new method, based on the frequency domain analysis, to measure dynamic
impedance of x-Si solar cells and PV modules in the dark using basic instruments and FFT
analysis. The dynamic parameters in the AC equivalent circuit, in addition to the DC model,
consists of dynamic resistance, diffusion capacitance and transition capacitance. Loci of
impedance in the complex plane can be obtained by inputting a small signal square wave,
superimposing on either forward bias or reverse bias, to cells or modules. Such technique is
compared with sinusoidal inputting. All of these parameters can be obtained from impedance
loci in the complex plane. The impedance of a cell or a module can be derived in a closed
form equation in terms of frequency dependent and voltage dependent resistance and
capacitance under the dark condition with reverse bias. The relationship between the dynamic
and static characteristics is compared for solar cell modules having low and high fill factors.
Another new analytical method determining solar cell and module dynamic impedance is
demonstrated using the same measuring techniques. Determination of dynamic parameters,
previously outlined, and time constant of solar cells and modules, based on a time domain
response, can be simultaneously obtained at each bias condition. The merits of this second
characterization method using square wave inputs are reduction in measuring steps and

yielding of dynamic parameters and time constants in a single measurement.
Experiments on polycrystalline and amorphous silicon cells and modules are also
conducted and their results will be separately revealed at a later date. Knowledge of dynamic
impedance characterization of solar cells and modules will lead to better understanding of
behaviors of PV grid-connected systems and improvement of power quality from such
distributed power generation systems.
Chapter 11 - Modern wind energy technologies rely heavily on the very complex
scientific discipline of fluid dynamics (which includes the study of the atmosphere) and the
equally complex engineering discipline of aerodynamics. A comprehensive treatment of
either of these disciplines is well beyond the scope of this programmatic environmental


Preface

xv

impact statement (PEIS). The discussions that follow are intended only to establish a basic
understanding of wind technology and the factors that control its evolution. References are
provided for those who wish to have a more detailed understanding of wind technology.
This appendix provides an overview of the fundamentals of wind energy and wind energy
technologies, describes the major components of modern wind turbines, and introduces terms
that are unique to the field of electric power generation using wind energy. Important site
characteristics and critical engineering aspects of wind energy technologies are presented, and
their respective influences on future development decisions are discussed.[1] An overview of
the current state of wind energy technology and ongoing research and development (R&D) is
provided. Descriptions of a typical wind energy project and the major actions associated with
each phase of development — site monitoring and testing, construction, operation, and
decommissioning — are presented in part 3 of this PEIS.
Chapter 12 - The tables that follow list the major federal and state laws, Executive
Orders, and other compliance instruments that establish permits, approvals, or consultations

that may apply to the construction and operation of a wind energy project on Bureau of Land
Management (BLM)-administered lands. The general application of these federal and state
authorities and other regulatory considerations associated with such construction and
operation are discussed in Chapter 3.
The tables are divided into general environmental impact categories. The citations in the
tables are those of the general statutory authority that governs the indicated category of
activities to be undertaken under the proposed action and alternatives. Under such statutory
authority, the lead federal or state agency may have promulgated implementing regulations
that set forth the detailed procedures for permitting and compliance.
Definitions of abbreviations used in the tables are provided here.
Chapter 13 - Data on commercial wind energy projects in the western states that are
within the scope of this programmatic environmental impact statement (PEIS) are displayed
in the tables below. The American Wind Energy Association (AWEA) compiles and
maintains all of the data displayed below. All data presented are current as of January 14,
2004. All data are accessible electronically from the AWEA Web site at
Data presented in the tables below are updated
quarterly by the AWEA.
The Bureau of Land Management (BLM) cannot guarantee the completeness or accuracy
of these listings. Submission by wind farm developers or operators of project information to
AWEA for inclusion in these listings is voluntary.
Chapter 14 - Forest biomass and bioenergy production currently play a very important
role in energy generation in tropical African countries, especially in the rural areas where
between 75 and 95% of the populace depend on fuelwood as the primary energy source.
Given the current high population growth, the low rates of switching to non-carboniferous
household energy sources as well as the inefficiency of other energy sources, the importance
of biomass and bioenergy in household energy generation in tropical African countries is
expected to increase in the future. This paper examines the sources and extent of biomass
production in tropical African countries as well as their current contribution to bioenergy
supply and possible future trend. The current status and prospects of bioenergy technologies,
the state of biomass and bioenergy research in the sub-region as well as the methodologies

used in obtaining local and national biomass estimates were reviewed. The paper also
discussed the challenges facing biomass and bioenergy research in tropical Africa, and


xvi

A. L. Zenfora

stressed the need for more collaboration with the developed countries to be able to tackle the
challenges. The paper finally examines the likely future research directions and makes
recommendations towards a more efficient and environmental-friendly utilization of biomass
and bioenergy in the sub-region.
Chapter 15 - Fast-growing broadleaf species (poplars, willows and black locust), raised in
dense, short-rotation plantations, very often on the soils unsuitable for agricultural crops,
produce a high yield of biomass. A significant amount of thermal energy can be obtained by
direct combustion of young plant biomass (aged from one to three years) converted into chips
by chipping the whole trees together with bark and branches.
In this aim, the Institute carried out systematic multiannual research on the improvement
of several poplar clones in order to increase the yield of biomass. Also for this purpose, the
selection focused on the clones which are best adapted to the conditions of very dense
planting, which is the main condition required from the foresters in the establishment of
energy plantations.
Based on the calorific value of wood and bark of the study poplar clones, it is assessed
the quantity of energy which could be produced by the combustion of the chipped biomass of
one-year, i.e. two-year-old plants. The higher heating value of wood and bark was determined
for several poplar clones (Populus spp.) of different ages and plants, as well as the trees from
mature plantings (aged from 8 to 14 years). By FVI (Fuel Value Index) which takes into
account ash content, wood basic density, as well as moisture content, it was determined that
poplar wood can be significant energy raw material, primarily because of its short production
cycle and very high volume increment.

The plantations are established in two variants, by planting the cuttings of the selected
poplar clones, with two planting spaces, i.e. with 38,461 plant/ha, and 83,333 plant/ha, on the
previously selected and prepared soil. To define the produced biomass of individual clones,
the increment elements were measured after the cycles of one and two years.
Average dry matter biomass yield reached 21 t ha-1 year-1 (38,461 plant/ha), and 12 t ha1 year-1 (83,333 plant/ha). Based on calorific values of oven dry wood and bark of each
clone, average energy potential of researched poplar clones was estimated up to 395 GJ ha-1
year-1, and for denser plantations up to 222 GJ ha-1 year-1.
Chapter 16 - Plants represent a natural chemical and polymer factory and food plant.
Biorefineries combines necessary technologies between biogenic raw material and
intermediates and final products. The paper present two strategies for producing of polymeric
materials, firstly the utilization of the pre-determined natural macromolecular structure and
secondly the using of biogenic building blocks. The first step is the fractionation technology
from green biomass for producing of fiber-rich press cake and a nutrient rich-green juice. The
main focus is directed on products, such as proteins, polylactic acid, cellulose and levulinic
acid- sequence products and their application as well as their market.
Chapter 17 - In this chapter a set joint of experimental techniques for assessing biomass
combustion devices is presented. Small scale energy converters such as chimneys, boilers,
stoves, etc, producing heat and/or hot water by combustion of biomass (wood, pellets,
briquettes, etc.) are especially suited to domestic purposes. However, in regular commercial
combustion conditions, this kind of use still has some disadvantages: besides the fact that
some emissions (volatile organic carbons, carbon monoxide or NOx) may still be high, it is
difficult to compare the quality and performance of equipment working in very different
combustion conditions.


Preface

xvii

Due to their relatively low cost and the complexity of combustion in such devices,

modelling by numerical analysis is seldom attempted. Controlling operational factors are
usually designed and regulated based on the manufacturer’s experience or on handbook
values. In order to protect customers, and to assure compliance with minimum requirements
for energy performance and maximum limits on pollutant emissions, several national and
international regulations have been developed in recent years. Experimental analysis of these
devices is a key technique for control and improvement.
Chapter 18 - Mitigation of and adaptation to climate change belong to the most pressing
global challenges for the 21st century. Major mitigation options include improved energy
efficiency, shifting towards less carbon-intensive fossil fuels, increased use of energy sources
with near-zero emissions, such as renewables and nuclear, CO2 capture and permanent
storage (CCS), and carbon sequestration by protection and enhancement of biological
absorption capacity in forests and soils.
Bioenergy is one of several energy sources which could provide society with energy
services with near-zero emissions. Bioenergy has a unique feature, however, which
distinguishes it from other low-emitting energy supply options, such as solar, wind, nuclear,
and clean fossil energy technologies. Bioenergy conversion could be integrated with a process
which separates carbon. If the biomass feedstock is sustainably produced and the separated
carbon is subsequently isolated from the atmosphere for a very long time the entire process
becomes a continuous carbon sink – in other words such technologies yield negative CO2
emissions. Negative emission biomass technologies can be centralised or distributed;
Centralised negative emission biomass technologies, biomass energy with CO2 capture and
storage (BECS), build on the conversion of biomass into energy carriers in centralised
conversion plants integrated with CO2 capture. The captured CO2 is subsequently transported
and stored in geological formations. Distributed negative emission biomass technologies are
based on the production of long-term carbon-sequestering charcoal soil amendment, with or
without co-production of biofuels.
In this chapter a BECS implementation scenario study is presented. The study analyses
investments in BECS in a pulp and paper mill environment. The investment analysis is
carried out within a real options framework taking into account the potential revenue from
trading generated emission allowances on a carbon market. Uncertainty is considered in the

economic modelling through the use of stochastically correlated price processes of one input
price (biomass) and two output prices (electricity and CO2 emission permits) that are
consistent with shadow price trajectories of a large-scale global energy model. The results
suggest that BECS can be economically feasible within approximately 40 years.
The chapter also discusses Research and Development needs for better understanding of
the future overall potential of negative emission biomass technology implementation.
Chapter 19 - There is a steady and continuing interest in biomass gasification in both the
developed countries and developing countries. While the advanced countries are interested
primarily from considerations of reduced emissions and waste utilisation, the developing
countries look at biomass gasification as a means to augment commercial energy like
electricity, diesel, fuel oil etc.
India, a tropical country with a vast geographical area is richly endowed with renewable
energy sources like solar, wind, biomass which can play a crucial role in meeting end use
energy needs in a decentralised manner. One of the major goals of the ninth and tenth five
year plan is strengthening of infrastructure (energy, transport, communication, irrigation) in


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order to support the growth process on a sustainable basis. It is usually the tendency of the
developing countries to equate development with economic growth and to further equate
economic growth with energy consumption especially electricity. India being a developing
country has also given due emphasis on strengthening its energy position accordingly.
Moreover threat from Green House Gasses (GHG) also has caused worldwide concern. In
India electric power generation is the largest source of GHG emissions. It accounts for 48%
of carbon emitted. These concerns point towards more rational energy use strategies. The
renewable and recycling process makes biomass possible to generate power without adding to
air emissions.

Biomass (firewood, agricultural residue, and dung) is one of the main fuels in India,
particularly in the energy-starved rural sector. The biomass power potential in India was
16,000 MW (excluding co-generation), but the achievement in this respect is negligible
(Installed capacity - 630 MW Project under implementation - 630 MW, as on March 2005). It
brings out the fact that much of the potential of biomass gasification is still unexplored.
Globally, India is in the fourth position in generating power through biomass and with a huge
potential, is poised to become a world leader in utilization of biomass.
According to the Planning Commission of India, in its Tenth Five Year Plan, announced
that 26.10 per cent of the Indian populations are below the poverty line and mostly belongs to
rural areas. The inequitable distribution has been evident from the fact that although 70% of
India’s population lives in the rural areas, only 29% of rural households have electricity
supply as against 92% of urban households. Of the half a million or so villages in India, about
3, 10,000 villages have been declared to be electrified and 80,000 more villages remain
completely un-electrified. There are a number of constraints to supply power to remote rural
area such as small human settlements, geographically dispersed villages, seasonally of loads
etc. In the absence of adequate network and hence supply of power to remote rural areas the
household depend largely on primary energy sources like kerosene and diesel for lighting. No
commercial investments in micro enterprises can therefore be made by either individuals or
companies without installing diesel generators which have a very high generating cost.
Biomass gasifier is a leading option in that respect. Besides, the supply of power to remote
rural areas from the centralised grid is not competitive than a modern biomass gasification
based decentralised power plant. Estimate from an Indian village shows that modest 50 kW of
installed capacity per village will lead to total saving of 52000 million Rs (Rs 5200 Crore /
1100 million US $) in power plant investments. In energy terms, the saving in TandD losses
will release a generation capacity of 800 MW for profitable sale. Reduced pollution and
reduction of CO2 emissions will be the other advantages of a decentralised renewable energy
based system for the rural areas.
The purpose of the present paper is to evaluate the rural electrification programme in
India undertaken by the Ministry of Non Conventional Energy Sources (MNES), Government
of India, through biomass gasifier power plant. It explores the eradication of poverty that has

been made possible by introducing biomass gasification based power plant in remote rural
areas in India. Creation of jobs in the power stations, small-scale business, commerce and
industries and also improvement in the quality of life is assessed. The paper concludes with
policy options relevance for the other developing countries.
Chapter 20 - In this study energy balance and fuel properties of biodiesel has been
calculated. Accordingly, the cost of 1 liter of oil is calculated 0.32 € after the income from the
seed meal is deduced. Finally, the cost of per unit of biodiesel (1 liter) was calculated as 0.55


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xix

€, after deduction of the income provided by the sales of glycerin for use in soap and cosmetic
industry.
The energy equivalent of total output was calculated 147605.50 MJ per hectare. The net
energy gain (refined oil) was found as 15105.63 MJ per hectare (The net energy ratio 11.031)
according to yield and inputs values.
The viscosity values of vegetable oils vary between 27.2 and 53.6 mm2/s whereas those
of vegetable oil methyl esters between 3.59 and 4.63 mm2/s. The flash point values of
vegetable oil methyl esters are highly lower than those of vegetable oils. The flash point
values of vegetable oil methyl esters are highly lower than those of vegetable oils. An
increase in density from 860 to 885 kg/m3 for vegetable oil methyl esters or biodiesel
increases the viscosity from 3.59 to 4.63 mm2/s and the increases are highly regular. There is
high regression between density and viscosity values vegetable oil methyl esters. The
relationships between viscosity and flash point for vegetable oil methyl esters are irregular.
An increase in density from 860 to 885 kg/m3 for vegetable oil methyl esters increases the
flash point from 401 to 453 K and the increases are slightly regular.
The LHV values of vegetable oils methyl ester vary between 35.74 and 39.16 MJ/kg.
Chapter 21 - Instability and increases in prices of petroleum-based fuels, gradual

depletion of world petroleum reserves and increases in environmental pollution caused by
exhaust emissions speed up research on renewable alternative fuels.
Vegetable oils have been considered as renewable alternative fuels in compression
ignition engines for a long time. However, they have not been widely used as fuels in the
engines due to some technical and economical drawbacks. Some properties of vegetable oils
such as high viscosity, lower volatility and lower heat content result in technical problems in
direct using of vegetable oils in short and long term applications. From economical point of
view, the main problem is that vegetable oils have been more expensive than petroleum
Diesel fuel.
There are various ongoing studies on solving these problems to be able to use vegetable
oils in Diesel engines. Different methods such as preheating oils, blending or dilution with
other fuels, thermal cracking/pyrolysis and transesterification have been developed. Among
these techniques, transesterification appears to be the most promising one. It is a chemical
process converting vegetable oils to alcohol ester of oil named as biodiesel. In general,
biodiesel-Diesel fuel No.2 blend can be used as a fuel in Diesel engines without modification.
Specifications of biodiesel mainly depend on oil, transesterification process, type and amount
of alcohol, type and amount of catalysis, reaction time and temperature.
Biodiesel can be produced from different kinds of vegetable oils. Since prices of edible
vegetable oils are higher than that of Diesel fuel No. 2, waste vegetable oils and non-edible
crude vegetable oils are mostly preferred as potential low priced biodiesel sources. It is also
possible to use soapstock, a by-product of edible oil production, for cheap biodiesel
production.
In this study, various biodiesels were produced from raw vegetable oils (rapeseed oil,
soybean oil, cotton seed oil, palm oil and tobacco seed oil), waste sunflower vegetable oils
and hazelnut oil soap stock-waste sunflower vegetable oil, and their specifications were
compared with each other. The biodiesel (20% in volume) - Diesel fuel No.2 (80% in
volume) blends were tested in a four cycle, four cylinder turbocharged indirect injection
Diesel engine. The effects of biodiesel addition to Diesel fuel No.2 on the performance and
emissions of the engine were investigated at full load. Experimental results showed that the

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biodiesels can be partially substituted for Diesel fuel No.2 at most operating conditions in
terms of performance parameters and emissions without any engine modification and
preheating of the blends.
Chapter 22 - Lignin, obtained through steam explosion from straw, was completely
characterized via elemental analysis, gel permeation chromatography, ultraviolet and infrared
spectroscopy, 13C and 1H nuclear magnetic resonance spectrometry.
Lignin powder was used for the preparation of blends with low-density polyethylene
(LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE) and
atactic polystyrene (PS).
The obtained blends are processable through the conventional techniques used for
thermoplastics; the modulus slightly increases for most lignin-polymer blends, while the
tensile stress and elongation reduce. Moreover, lignin acts as a stabilizer against the UV
radiation for PS, LDPE and LLDPE.
Polyurethanes were obtained treating steam exploded lignin from straw with 4,4’methylenebis(phenylisocyanate), 4,4’-methylenebis(phenylisocyanate) – ethandiol, and
poly(1,4-butandiol)tolylene-2,4-diisocyanate terminated. The obtained materials were
characterized by using gel permeation chromatography, infrared spectroscopy and scanning
electron microscopy. Differential scanning calorimetry analysis showed a Tg at -6 °C,
assigned to the glass transition of the poly(1,4-butandiol) chains. The presence of ethylene
glycol reduced the yields of the polyurethanes. The use of the prepolymer gave the best
results in polyurethanes formation. Steam exploded lignin was used as starting material in the
synthesis of polyesters. Lignin was treated with dodecanoyl dichloride. The products were
characterized by using gel permeation chromatography, infrared spectroscopy, 13C and 1H
nuclear magnetic resonance spectrometry, and scanning electron microscopy.
Chapter 23 - Pilot plant experiments with both a 3.79 m3 batch and semi-continuous
reactor have been performed with whole, fresh swine manure and the production of

biochemical energy as heat has been both measured and calculated. The reactor operates at
near atmospheric pressure and about 55˚ C. The systems were equipped with a patented
offgas recycle process that may be shown to increase the amount of recoverable and useful
energy from the reactor compared with a once-through aeration system. The batch study, a
statistically-designed series of experiments, was held to investigate the relationships of initial
or feed total solids concentration, fresh air fed, and offgas recycle rate to the total biochemical
energy produced in the system. A linear model was developed to determine the importance of
these factors in design. The model indicates optimism for improved operation over pilot plant
work performed. The recycle concept is most useful when a reactor design is desired with a
relatively shallow depth (e.g., 3 m aeration submergence), as may be found in in-ground
concrete tanks. Good results may be achieved in deep aeration submergence reactors with no
offgas recycle, owing to the higher oxygen transfer efficiencies in tall tanks. A combination
of tall tanks and offgas recycle is synergistic with improved results. These results will be
presented and discussed in the context of a full-scale farm application. When compared to
once-through aeration systems, offgas recycle also leads to major reductions of emitted
offgas, and aiding odor and pollutant reductions. Other potential applications will also be
discussed.
Chapter 24 - The design, operation and control of highly risky industrial systems, such as
in the nuclear, chemical and aerospace, entail the capability of accurately modelling the


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nonlinear dynamics of the underlying processes. In this respect, Artificial Neural Networks
(ANNs) have gained popularity as valid alternatives to the lengthy and burdensome analytical
approaches to reconstructing complex nonlinear and multivariate dynamic mappings.
In particular, Recurrent Neural Networks (RNNs) are attracting significant attention,
because of their intrinsic potentials in temporal processing, e.g., time series prediction, system

identification and control, temporal pattern recognition and classification, whereas classical
feedforward neural networks are in general capable of representing only static input/output
mappings.
The aim of this chapter is to present two kinds of recurrent neural networks and show
their capabilities of approximating the temporal evolution of complex dynamical systems.
First, the Elman’s recurrent network is considered, in which external feedback
connections feed the output of the hidden nodes back to a set of additional nodes placed in the
input layer. The network’s modelling capabilities are demonstrated on a case study
concerning the prediction of the behaviour of a steam generator in a nuclear power plant.
A more advanced type of recurrent architecture is then presented: the Infinite Impulse
Response-Locally Recurrent Neural Network (IIR-LRNN), characterized by nodes which
contain local, internal feedback paths realized by means of IIR synaptic filters providing the
network with the necessary system state memory. The effectiveness and criticalities of this
type of recurrent neural network are tested on two highly nonlinear dynamic systems of
literature, the discrete-time Back-Tsoi model and the continuous-time Chernick model
describing the evolution of the neutron flux in a nuclear reactor.
Chapter 25 - A new method for primary cosmic ray investigations based only on
atmospheric Cherenkov light flux analysis is presented. The method is applied for the
solution of two of the main problems in astroparticle physics: ground based gamma ray
astronomy, selection of events initiated by primary gamma quanta and the energy and mass
composition estimation of primary cosmic ray in the region around the “knee”. The lateral
distribution of atmospheric Cherenkov light flux in extensive air showers initiated by primary
proton, Helium, Oxygen and Iron nuclei with energies in the range from 1013 eV to 1017 eV
were obtained with the help of the CORSIKA 5.62 code, using VENUS and GHEISHA
hadronic interaction models for the Chacaltaya observation level of 536 g/sm2.
The lateral distribution of Cherenkov light flux in extensive air showers is approximated
using a nonlinear fit such as Breit-Wigner. A detailed study of the energy dependence of the
proposed model function parameters is carried out and the fit of model parameters as a
function of the energy is obtained as well. On the basis of the difference between the model
parameters, precisely their behavior as a function of the energy, the strong nonlinearity of the

model, the authors propose a method, which permits the making of the distinction between a
primary gamma quanta from a primary nuclei. The efficiency of the method is estimated and
studied.
An additional analysis for primary nuclei is carried out, towards the development of a
similar method for simultaneous energy and mass composition estimation of simplified
cosmic ray spectra of protons, iron, helium and oxygen.
Different detector displacements are analyzed using the simulation of simplified primary
mass composition. The detector response is simulated taking into account the physical
fluctuations of the processes, the statistical and possible systematic errors. The simulated and
reconstructed events are compared and the accuracy in energy and primary mass estimations


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is obtained. Moreover, the accuracy in shower axis localization is studied and the
corresponding criteria are proposed.
On the basis of the obtained approximation of the lateral distribution of Cherenkov light,
a fast Monte Carlo simulation of the response of a different detector displacement is carried
out. The possible triggers for two different detector arrays are studied and the registration
efficiency is estimated.
Chapter 26 - The paper presents the development of a sub-channel thermal hydraulic
analysis code named SUBCHAN. The code was originally developed to analyze a super
critical CANDU type reactor which has such characteristics as horizontal fuel channels,
heavy water moderated, super critical light cooled water, and any type of fuel bundle with or
without thorium rods. Thermal-hydraulic model of SUBCHAN is based on four partial
differential equations that describe the conservation of mass, energy and momentum vector in
axial and lateral directions for the water liquid/vapor mixture. The heat transfer correlations
and pressure drop correlations used in the SUBCHAN code are presented in this paper. The

water properties package of the code is based on the Industrial Formulation 1997 for the
Thermodynamic Properties of Water and Steam. The heat transfer correlation of super critical
region is based on the experimental investigation of Xi'an Jiaotong University. By calculating
the TACR case, which is operating at 12.5MPa pressure, compared with the results of
ASSERT-PV code, the paper arrives at the conclusion that the development of the
SUBCHAN code with super critical water property package is successful. Then the paper
uses the SUBCHAN code to analyze CANDU-SCWR operating at 25.0 MPa pressure. The
paper draws the conclusion that the SUBCHAN code can be used to analyze sub-channel
thermal hydraulic analysis of CANDU-SCWR fuel channel.
Chapter 27 - Computer codes are widely used for Nuclear Power Plants (NPP) safety
analysis within a wide set of purposes including licensing issues, safety improvement
programs of existing NPPs, better utilization of nuclear fuel, and higher operational
flexibility, for justification of lifetime extensions, development of new emergency operating
procedures, analysis of operational events, and development of accident management
programmes. A safety key parameter of the evaluation and assessment of NPPs is closely
related to the code ability in determining the time-space thermal-hydraulic conditions
throughout the reactor coolant system and especially in the core region. In the beginning, the
code development took place between the sixties and seventies during which sets of
conservative models were used. Furthermore, the latter were also limited due mainly to the
restricted computer memory, Central Process Unit (CPU) time, and performances. However,
in light of the sustained development in computer technology and computational methods, the
potential of computational features has been enlarged accordingly. Nowadays, it has become
possible to switch to a new generation of computational tools consisting of coupling advanced
computer codes and getting better realistic simulations of complex phenomena and transients
that could occur in NPP. These packages include mainly a thermal-hydraulic system and
reactor kinetics codes, as well as specific codes for the containment thermal-hydraulics,
structural mechanics codes, and more sophisticated Computational Fluid Dynamics (CFD)
codes.
However, notwithstanding the complexity of these codes and the level of the present
scientific knowledge, a computer code cannot be expected to accurately model phenomena

that are not yet fully understood by the scientific community. In general, the results of code
predictions, specifically when compared with experimental data, often reveal some


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xxiii

discrepancies. These discrepancies could be attributed to several reasons as model
deficiencies, approximations in the numerical solution, nodalization effects, imperfect
knowledge of boundary and initial conditions. Therefore, it is necessary to investigate the
uncertainty of the results and the sensitivity effect of the most effective parameters.
The purpose of the present paper is to characterize the present situation as far as the code
assessment and uncertainty predictions are concerned. This is achieved through a reevaluation of some typical activities carried out at the University of PISA. These examples
concern mainly application of Best Estimate tools for PWR, BWR, VVER1000 and Research
nuclear reactors accident analysis. On this basis, requirements and future needs in the field of
Best Estimate tools are outlined.
Chapter 28 - Most of the studies and experiments on nuclear fusion are currently devoted
to the Deuterium-Tritium (DT) fuel cycle, the easiest way to reach ignition. Some of the main
technological questions of future DT fusion reactors have been identified previously. Among
those, in particular, the radioactive inventory in such reactors is due, besides tritium, to the
neutron-induced radioactivity in the reactor structures. The recent stress on safety by the
world community has stimulated research on fuel cycles other than the DT cycle, based on
‘advanced’ reactions, such as Deuterium-Helium-3 (DHe). Several studies have addressed the
design of DHe reactors: concerning small-size near-term experiments, to begin to explore the
possibilities of DHe plasmas, a DT burning plasma experiment at high magnetic field and
high plasma densities is particularly compelling.
Ignitor is a proposed compact high magnetic field tokamak, aimed at reaching ignition in
DT plasmas and at studying them for periods of a few seconds. A design evolution of Ignitor
in the direction of a reactor using a DHe fuel cycle has been proposed: a feasibility study of a

high-field DHe experiment of larger dimensions and higher fusion power than Ignitor, still
based on the core Ignitor technologies, has led to the proposal of the Candor fusion
experiment.
This paper deals with the radioactive waste issue for fusion reactors, proposing an
innovative solution (the “zero-waste” option), which is a clear advantage of fusion power
versus fission, in view of its ultimate safety and public acceptance. Even if feasible in theory,
a zero-waste option for fusion reactors using the DT fuel cycle will be difficult to obtain. As a
further step towards the zero-waste option, the features of fusion reactors based on alternative
advanced fuel cycles have been examined, to assess whether that goal could be reached for
such devices. Fusion reactors with advanced DHe fuel cycle turn out to have quite
outstanding environmental advantages.
Activation behaviour of materials after service in a DHe advanced fuel fusion experiment
has been investigated. EUROFER, SiC/SiC and V-Cr-Ti materials have shown the possibility
of being declassified to non-radioactive material (clearance) after their irradiation in the
reactor plasma chamber wall, if a sufficient interim cooling time is allotted. AISI 316L, on the
contrary, suffers the presence of Ni and N (alloying elements) and Nb and Mo (impurities).
Chapter 29 - A "dynamic" solar power plant (which consists of a solar collector - thermal
engine combination) is proposed as an alternative for the more usual photovoltaic cells. Upper
bounds for the efficiency of solar thermal power plants operating in the Martian environment
are first evaluated. A general thermodynamic approach, first presented here, clearly shows
which of the three theories usually quoted in literature gives the exergy of thermal radiation.
Recent works reporting accurate upper bounds for the efficiency of thermal radiation energy
conversion into work are subsequently used in this chapter. The results refer to thermal


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engines powered by direct or diffuse solar radiation on Mars. Diffuse solar radiation is

modeled as diluted or multiply scattered thermal radiation. A more elaborated model uses an
endoreversible Carnot cycle to describe solar engine operation. Two strategies to collect solar
radiation are analyzed: a solar horizontal collector and a solar collector whose tilt and
orientation are continuously adjusted to keep the receiving surface perpendicular on Sun rays.
Meteorological data measured at Viking Landers (VL) sites are used in computations. Results
show that generally the influence of latitude on performance is important. In some situations
the meteorological effects compensate the latitudinal effects and the output power is quite
similar at both VL1 and VL2 sites. During a winter dust-storm day the maximum output
power is much smaller than during autumn. High efficiency thermal engines should be used
in combination with solar collectors kept perpendicular to the Sun’s rays. When a horizontal
solar collector is considered, the dependence of the maximum output power on optimum solar
efficiency seems to be quadratic at both VL1 and VL2 sites. When a collector perpendicular
to the Sun’s rays is considered, this dependence is more complicated, but keeps the quadratic
feature. No obvious difference exists between power plant performances in the two years of
VL2 operation. A solar Stirling engine based on a horizontal selective flat-plate converter is
analyzed in the last part of this chapter. All the computations were performed for a solar
collection area similar in size with that of Mars Pathfinder’s Sojourner. The solar efficiency at
noon is as high as 18 %. The power provided by the engine is as high as 16 W during autumn
and winter. These results suggest that under the Martian environment the performance of
properly designed solar Stirling engines is comparable with that of PV cell power systems.
Chapter 30 - Zirconium has a low neutron capture cross-section and it is used in alloys
for internal components of nuclear reactors, the currently named Zircaloy, Zr-Nb, ZIRLO,
etc. In Zircaloy-2 and Zircaloy-4, chromium is an important component in order to assure
good corrosion performance, and tin is one of the strengthening elements. On the other hand,
titanium, in spite of its poor neutron transparency, has sometimes been considered an element,
which could substitute zirconium in this kind of alloy.
The present experimental study concerns two ternary systems Zr-Cr-X (being the X
component Sn or Ti). Published data on phase equilibriums of these systems are very scarce
and found only in Russian works.
Many contributions to the knowledge of phase equilibriums in ternary and quaternary

systems involving zirconium as the principal component were assessed by Ivanov O.S. et al.
and published by the Metallurgical Institute of Moscow in the monograph Zirconium Alloys
Structures in 1973. Stability domains of phases at different temperatures of those two
ternaries were presented, especially as isothermal sections of the equilibrium diagram.
The knowledge of transformations through equilibrium diagrams is essential in order to
design or improve technological applications, especially in the temperature range where the
Zr rich hcp/bcc solid solution reaction is possible.
Alloys were prepared by melting the metal components in a non-consumable tungsten
electrode arc furnace with a copper crucible under a high purity argon atmosphere.
Phase characterizations and determination of their compositions were carried out by
metallographic observations and electron microprobe analysis. X-ray diffraction was
performed on some samples.
The study of the Zr-Cr-Sn system involves alloys with compositions between 0 and 15 at.
% Cr and 0 to 15 at. % Sn and heat treatments at temperatures of 860, 900, 960 and 980 ºC.