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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Physical Characteristics of Soil Receiving Attention

Amburgey, Lyman 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
102

Increasing Interest in Precision Tillage

Larsen, W. E. 02 1900 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
103

IN SITU ELECTROKINETIC SAMPLE PREPARATION FOR SELF-ASSEMBLED MONOLAYER BASED ELECTROCHEMICAL BIOSENSING

Sin, Lai Yi Mandy January 2011 (has links)
Electrokinetics based microfluidic systems are potentially promising for lab-on-a-chip applications due to their effectiveness in manipulating nanoscale and biological objects, label-free operation, simple fabrication processes, small voltage requirements, and most importantly simple system integration strategy. Among various electrokinetics techniques, AC electrothermal flow (ACEF) is the most promising technique in microfluidic manipulation toward biomedical applications due to its effectiveness in high conductivity biological and physiological fluids. As relatively little is known about the ACEF induced fluid motion at highly conductive samples, the characteristics of electrothermal manipulation of fluid samples with different conductivities were investigated systematically. For low conductivity sample (below 1 S/m), the characteristics of the electrothermal fluid motion was in quantitative agreement with the theory. For high conductivity samples (greater than 1 S/m), the fluid motion appeared to deviate from the model as a result of electrochemical reactions and the temperature effect. Here, a universal electrode approach which directly implements ACEF-induced sample preparation on a SAM based electrochemical sensor for point-of-care diagnostics of urinary tract infections has also been demonstrated. Using uropathogenic E. coli clinical isolates as model systems, we demonstrate that "on-chip" ACEF-induced sample preparation can improve the sensor performance without complicated system integration strategy and presents a pathway for implementing truly lab on a chip, instead of chip in a lab. Finally an integrated chip approach has been proposed for transforming electrochemical sensing system from laboratory research into point-of-care diagnostics with multiple microelectrodes.
104

EPR studies of carbohydrate-derived free radicals and alkene polymerisation

Ward, Steven Richard January 1999 (has links)
No description available.
105

Preparation and characterisation of magnetoresistive materials

Cohen, Neil Stephen January 1998 (has links)
No description available.
106

Intentions and Implementation of the Professional Development and Appraisal System in Texas

Davis-Frost, Diane 12 1900 (has links)
The purpose of this study was to describe the intentions of the designers of the Professional Development and Appraisal System (PDAS) in Texas and the perceptions of teachers regarding its implementation. Information for the study was gathered in two phases using two methodologies. The first was a semi-structured interview with four expert informants instrumental in the design and implementation of the PDAS at the state level. The second component of the study was conducted with teachers using a 37-item Likert survey. The population for this phase of the study was 150 elementary and 150 secondary teachers chosen randomly from three school districts in North Central Texas. The districts were selected to represent a variety of sizes in regard to student population and represent diverse student population characteristics and socioeconomic levels. Data from the semi-structured interviews and the returned surveys were analyzed to determine the designers' intentions and areas of emphasis and to describe the alignment the teachers' perceptions and the designers' intentions. Quantitative data gathered from the surveys were analyzed using descriptive statistics as well as a correlation and function analysis and analysis based on a Cronbach alpha coefficient. The analysis of data revealed the following: 1. Teachers perceived that the implementation of the PDAS has a high level of effect in the areas of learner-centered instruction; classroom management; support for all students; the professional growth of teachers; communication; learning application; and, TAAS improvement. 2. Teachers' perceptions were not affected by years of experience. 3. Teachers' perceptions were not affected by their field of instruction. One implication of this study is that the final design represents the intentions of designers, although the area of student achievement is not weighted as heavily in teachers' evaluations as was originally intended. Furthermore, education leaders in Texas may conclude that teachers perceive a high level of impact upon their classroom practices as a result of implementation of the PDAS instrument. If future research reveals that the perceived impact is accurate and that classroom practices of teachers did change as a result of the instrument's implementation to the degree perceived, then this is a model for policy implementation at the state level that is extremely effective. Furthermore, additional researchers may investigate the link between classroom practices and student achievement. This research study is a first step toward describing effective, replicable practices.
107

Education preparation: knowledge and attitudes of msw students toward Acquired Immune Deficiency Syndrome and sexually transmitted diseases

Okoh, Nacole 01 May 1991 (has links)
This study describes and compares the results of a survey of 53 masters of social work students to determine the nature and extent to which their educational preparation included instruction on acquired immune deficiency syndrome and sexually transmitted diseases. The study also assessed the social work students' attitudes toward people with HIV/AIDS and STDs, as well as their attitudes toward the role of social work education and the profession in addressing the HIV/AIDS and STD epidemics. To obtain this purpose the investigator developed a 56-item questionnaire. One of five hypotheses generated was accepted. Results showed that social work students need to increase their exposure to HIV/AIDS and STD related issues.
108

A study of the sol-gel system for the preparation of mullite

Oluwa, Omoyele A. 01 December 1996 (has links)
Sol-gel processing methods were used to prepare mullite ceramic powder form high purity aluminum tri-sec butoxide and tetraethylorthosilicate solutions under different processing conditions. the effects of the processing conditions on the sol to gel transition were examined by varying the water ratios, pH and temperature. Prehydrolysis of the silicon alkoxide was used since the aluminum alkoxide reacts faster than the silicon alkoxide. It was observed that the variation in temperature has the greatest effect on the time to gelation for the precursors. The rheological properties during the aging process indicated an increase in viscosity with age time, which is consistent with change in structure. Measurements of the viscoelastic properties during the sol to gel period showed a predominance of the loss (viscous) modulus over the storage (elastic)modulus in the initial stages of stages of aging. With increased aging of the sols and gels, large elastic components were observed which is consistent with structure build-up. The changes in structural evolution were followed by Fourier Transform Infra-red spectroscopy and correlated well to changes in the rheological properties of the sol. TG/DTA and X-ray analyses were used to correlate the starting chemistry and reaction condition to the microstructure of the final mullite powder. In all experimental cases fine grain mullite powder were obtained indicating no apparent differences of the synthesis conditions on the final mullite powder microstructure.
109

Teachers of Students with Emotional and Behavioral Disorders’ Perceptions of Professional Standards of Practice

Lusk, Mandy E. 08 1900 (has links)
In recent decades, there has been renewed interest in examining the effectiveness of teacher preparation programs. Unfortunately, researchers have found that there is limited empirical research on the effectiveness of quality special education teacher preparation programs, specifically those programs specializing in the education of students with emotional and behavioral disorders (EBD). The Council for Exceptional Children (CEC), the largest special education organization, conducts research on the standards needed by teachers who serve children and youth with exceptionalities. These CEC standards are recommended to serve as a guide for teacher preparation programs in special education. Utilizing the CEC standards delineated for preparation programs in EBD, the present study sought to determine how graduates of one program perceived the importance of the standards and their perceived proficiency in using the standards in their work with students with EBD. Results indicated that graduates viewed the standards as Important to their work with students with EBD. Further, they viewed their proficiency in using the standards to be above average. In addition, the present study examined the relationship between graduates perceived importance and perceived proficiency in using the CEC standards. Results indicated that graduates who had higher score ratings on their perceived importance of the standards tended to have higher ratings on their perceived proficiency scores.
110

Preparing Early Childhood Special Educators for Inclusive Practice

Hooper, Belinda 22 April 2011 (has links)
The purpose of this study was to describe experienced practitioners’ beliefs about inclusion and their perceptions of what early childhood special education (ECSE) preservice teachers need to know and be able to do to effectively support early childhood inclusion. This study used a sequential explanatory mixed methods approach to describe the perceptions of ECSE practitioners currently participating in the Virginia Department of Education (VDOE) statewide initiative, Inclusive Placement Options for Preschoolers (IPOP). The study occurred in two stages: 1) a survey of ECSE IPOP planning team members, and 2) focus group interviews with ECSE IPOP planning team members. Data were analyzed using statistical and qualitative methods and interpreted through the Learning to Teach in Community framework. This study provides an understanding of how early childhood inclusion is actualized in practice in one state seeking to systematically increase the inclusive placement options available for preschool age children with disabilities.

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