Increasing the power conversion efficiency (PCE) of silicon solar cells by improving their junction properties or minimizing light reflection losses remains a major challenge. Extensive studies were carried out in order to develop an effective antireflection coating for monocrystalline solar cells. Here we report on the preparation of a nanostructured cerium oxide thin film by pulsed laser deposition (PLD) as an antireflection coating for silicon solar cell. The structural, optical, and electrical properties of a cerium oxide nanostructure film are investigated as a function of the number of laser pulses. The X-ray diffraction results reveal that the deposited cerium oxide films are crystalline in nature and have a cubic fluorite. The field emission scanning electron microscope investigations show an increase in the film grain size with increasing the number of laser pulses. The carrier concentration of the film decreases and the mobility increases as the number of laser pulses increases. The cerium oxide film deposited on silicon at 900 laser pulses exhibits a minimum optical reflection. The maximum PCE was 19.27% and fill factor of 87% was obtained after the deposition of silicon solar cell with cerium oxide nanostructured film deposited at 1000 laser pulses.
Objectives: To identify child or family related risk factors for
unintentional childhood poisoning in Sulaymaniyah, Iraq and to suggest
possible causes and preventive measures.
Methods: This is an epidemiological description and a case-control study. The study was undertaken in Sulaymani ,in 2004-2005. Cases were 200 children who were admitted to the hospital for treatment of poisoning. For every case two controls were selected. Al l parents of the children were interviewed by using a questionnaire that incl uded demographic and poisoning characteristic information.<
... Show MoreIsthmus life and prepare for it
The extracting of personal sprite from the whole image faced many problems in separating the sprite edge from the unneeded parts, some image software try to automate this process, but usually they couldn't find the edge or have false result. In this paper, the authors have made an enhancement on the use of Canny edge detection to locate the sprite from the whole image by adding some enhancement steps by using MATLAB. Moreover, remove all the non-relevant information from the image by selecting only the sprite and place it in a transparent background. The results of comparing the Canny edge detection with the proposed method shows improvement in the edge detection.
The significant shortage of usable water resources necessitated the creation of safe and non-polluting ways to sterilize water and rehabilitate it for use. The aim of the present study was to examine the ability of using a gliding arc discharge to inactivate bacteria in water. Three types of Bacteria satisfactory were used to pollute water which are Escherichia coli (Gram-negative), Staphylococcus aurous (Gram-positive) and salmonella (Gram-negative). A DC power supply 12V at 100 Hz frequency was employed to produce plasma. pH of water is measured gradually during the plasma treatment process. Contaminated water treated by gliding arc discharge at steadying the gas flow rate (1.5 l/mi
The set of all (n×n) non-singular matrices over the field F this set forms a group under the operation of matrix multiplication. This group is called the general linear group of dimension over the field F, denoted by . The determinant of these matrices is a homomorphism from into F* and the kernel of this homomorphism was the special linear group and denoted by Thus is the subgroup of which contains all matrices of determinant one.
The rational valued characters of the rational representations written as a linear combination of the induced characters for the groups discuss in this paper and find the Artin indicator for this group after study the rational valued characters of the rational representations and the induce
... Show MoreA new concrete rheometer is introduced including its innovation, actual design, working rules,
calibration, and reliability. A modified design of Tattersall two-point device is created. Some of
components are purchased from local and foreign markets, while other components and the
manufacturing process are locally fabricated. The matching viscosity method of determining the mixer
viscometer constants is demonstrated and followed to relate torque and rotational speed to yield stress
and viscosity (Bingham parameters). The calibration procedures and its calculation are explained.
Water is used as a Newtonian fluid, while; cement paste (cement + water) with w/c ratio equal to
(0.442) is used as a non-Newtonian fluid. Th
The study aimed to identify the future thinking skills of university students and which of these skills are prevalent. The sample of the study consisted of (400) male and female students from the university students. In order to achieve the goals of the research, the researcher built a measure of future thinking skills based on Torrance theory (2003). Psychometric properties of the standards were extracted, which are represented by honesty and consistency and the application of the measures to the research sample. The researchers found that Future thinking skills of university students, and that the skill of future planning is the most common skill among the research sample.
The she/teacher is considered one of the basics of the educational process for its essential role in education and teaching the kindergarten child, thus its lack to construct social relations in side the kindergarten environment working in it regarded one of the shortcoming factors she is suffering from which should be manipulated, because it could effect its enthusiasm to work in the kindergarten according to what has mentioned, the researcher presents the following objective:-
- Identifying level of social enhancement for the kindergarten teachers via the test of the following hypothesis:-
Programs directed to children through the media in general and in television in particular are among the main factors that help in forming the cultural and educational values of this important segment of society, and in light of this the study problem was identified in answering a major question: What are the cultural and educational values that Ajyal channel seeks Space planted in children through my program, Iftah Ya Simsim (in its new season) and Friends of Ajyal? , While the objectives of the study were evident in identifying the most prominent cultural and educational values that the Ajyal satellite channel worked to instill in children, and identifying the nature of the techniques used by Ajyal channel in providing the value conten
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