Studies on the morphology transition of micro-crystal growth in polymer films in high vacuum and strong electrostatic field

The morphology of films of isotactic polypropylene poly (3-dodecylthiophene) and iPP/P3DDT blend formed in electrostatic fields has been investigated by using scanning electron microscope. The experiment results show that the micro-crystal morphology of polymer films was strongly dependent on electrostatic fields. It was found that the effect of the electrostatic field led to the formation of dendrite crystals aligned in the field direction, and some branches of P3DDT ruptured. However, the micro-crystals in these films grew into spherulites without electrostatic field,and have no crystal orientation.

Determination of the impurities elements in high-purity cadmium by inductively coupled plasma mass spectrometry

A method for the determination of impurity elements in high purity cadmium by inductively coupled plasma mass spectrometry was developed. The spectral interference arising from Cd was discussed and the magnitude of interference by the polyatomic ion of Cd was compared. The effect of the high concentration Cd on the analyte signal was studied. The results showed that Cd possessed both significant suppression effects on the light mass elements signal and enhancement effects on the heavy mass elements signal,and the effects can be corrected by the use of internal standard elements. In this paper, Y and Bi was employed for the light mass elements and the heavy mass elements,respectively. As, Be, Co, Cu, Ga, Ge, Mn, Mo, Pb, Ni, Sr, Au, Tl, Th, V and U in high purity cadmium were determined. Detection limits are 0.005-0.052 mu g L-1,and the recoveries of standard addition are 82%-108%.

MODIFICATION OF POLYTETRAFLUOROETHYLENE BY RADIATION .1. IMPROVEMENT IN HIGH-TEMPERATURE PROPERTIES AND RADIATION STABILITY

Polytetrafluoroethylene (PTFE) has never been reported to form a network structure when subjected to high energy radiation. Results obtained in this work indicates that when irradiation is performed under 330-340-degrees-C in vacuo PTFE can be crosslinked

DETERMINATION OF TRACE AMOUNT OF 14 RARE-EARTH IMPURITIES IN HIGH-PURITY YTTRIUM-OXIDE WITH ICP-AES

A method of analysis of high purity yttrium oxide with ICP-AES was described with emphasis on the study of Y_2O_3 matrix effects. The results showed that the line intensities of ana]ytes decreased with the increase of Y_2O_3 concentration in solution because of following factors. (1) The presence of matrix resulted in the decrease of the amount of analytes reaching ICP. (2) Matrix Y_2O_3 entering the plasma decreased the excitation temperature of the plasma and depressed the ionization of analytes in the pl...

A Project on Developing Catholic Liturgical Music in Vietnam

Abstract unavailable.

Understanding teacher collaboration in disadvantaged urban primary schools: uncovering practices that foster professional learning communities

This study is set in the context of disadvantaged urban primary schools in Ireland. It inquires into the collaborative practices of primary teachers exploring how class teachers and support teachers develop ways of working together in an effort to improve the literacy and numeracy levels of their student. Traditionally teachers have worked in isolation and therefore ‘collaboration’ as a practice has been slow to permeate the historically embedded assumption of how a teacher should work. This study aims to answer the following questions. 1). What are the dynamics of teacher collaboration in disadvantaged urban primary schools? 2). In what ways are teacher collaboration and teacher learning related? 3). In what ways does teacher collaboration influence students’ opportunities for learning? In answering these research questions, this study aims to contribute to the body of knowledge pertaining to teacher learning through collaboration. Though current policy and literature advocate and make a case for the development of collaborative teaching practices, key studies have identified gaps in the research literature in relation to the impact of teacher collaboration in schools. This study seeks to address some of those gaps by establishing how schools develop a collaborative environment and how teaching practices are enacted in such a setting. It seeks to determine what skills, relationships, structures and conditions are most important in developing collaborative environments that foster the development of professional learning communities (PLCs). This study uses a mixed method research design involving a postal survey, four snap-shot case studies and one in depth case study in an effort to establish if collaborative practice is a feasible practice resulting in worthwhile benefits for both teachers and students.

Clinical autonomy and nurse/physician collaboration in emergency nurses

Aim: To investigate clinical autonomy and Nurse/Physician collaboration among emergency nurses and the relationship between these concepts, personal characteristics and organisational influences. Background: Nurses have been identified as having a significant role in addressing the challenges of providing modern healthcare. Emergency nurses have reported competence in a wide range of emergency care skills. However, there is evidence that Emergency Department (ED) nurses may have lower levels of clinical autonomy than other areas of practice. Levels of clinical autonomy appear to be influenced by levels of collaboration with physicians and the organisations in which nurses work Methods: A descriptive correlational study using a survey design with a purposive convenience sample of 141 ED staff nurses (response 70.9%) from 3 EDs in Ireland. Data were collected using the Dempster Practice Behaviours Scale (DPBS) the Nurse/Physician Collaboration Scale (NPCS) and the newly developed Organisational Influences on Nursing Scale. Demographic information was also sought from participants. Results: Participants were largely female (87%), relatively young (mean age 35.57, SD=7.83) and educated to degree level (48%) or higher (31%) with 40% posessing specialist emergency nursing qualifications. Participants reported moderate levels of clinical autonomy and Nurse/Physician collaboration. No relationships were found between sample characteristics and clinical autonomy and Nurse/Physician collaboration among emergency nurses. Relationships were found between levels of clinical autonomy and Nurse/Physician collaboration (r=-0.395, n=100, p<0.001), and organisational influence on nursing (r=0.455, p<0.001) and also between Nurse/Physician collaboration and organisational influence on nursing (r=-0.413, p<0.001). Discussion: Clinical autonomy of nurses has been linked with quality outcomes in healthcare. The quest for quality in modern healthcare in a challenging environment should acknowledge that strategies need to focus beyond education and skills provision and include essential elements such as Nurse/Physician collaboration and the organisational influence on nursing to ensure the greater involvement of nurses in patient care.

Physico-chemical properties and component interactions in high solids food systems

The present study aimed to investigate interactions of components in the high solids systems during storage. The systems included (i) lactose–maltodextrin (MD) with various dextrose equivalents at different mixing ratios, (ii) whey protein isolate (WPI)–oil [olive oil (OO) or sunflower oil (SO)] at 75:25 ratio, and (iii) WPI–oil– {glucose (G)–fructose (F) 1:1 syrup [70% (w/w) total solids]} at a component ratio of 45:15:40. Crystallization of lactose was delayed and increasingly inhibited with increasing MD contents and higher DE values (small molecular size or low molecular weight), although all systems showed similar glass transition temperatures at each aw. The water sorption isotherms of non-crystalline lactose and lactose–MD (0.11 to 0.76 aw) could be derived from the sum of sorbed water contents of individual amorphous components. The GAB equation was fitted to data of all non-crystalline systems. The protein–oil and protein–oil–sugar materials showed maximum protein oxidation and disulfide bonding at 2 weeks of storage at 20 and 40°C. The WPI–OO showed denaturation and preaggregation of proteins during storage at both temperatures. The presence of G–F in WPI–oil increased Tonset and Tpeak of protein aggregation, and oxidative damage of the protein during storage, especially in systems with a higher level of unsaturated fatty acids. Lipid oxidation and glycation products in the systems containing sugar promoted oxidation of proteins, increased changes in protein conformation and aggregation of proteins, and resulted in insolubility of solids or increased hydrophobicity concomitantly with hardening of structure, covalent crosslinking of proteins, and formation of stable polymerized solids, especially after storage at 40°C. We found protein hydration transitions preceding denaturation transitions in all high protein systems and also the glass transition of confined water in protein systems using dynamic mechanical analysis.

Infant milk formula manufacture: process and compositional interactions in high dry matter wet-mixes

Infant milk formula (IMF) is fortified milk with composition based on the nutrient content in human mother's milk, 0 to 6 months postpartum. Extensive medical and clinical research has led to advances in the nutritional quality of infant formula; however, relatively few studies have focused on interactions between nutrients and the manufacturing process. The objective of this research was to investigate the impact of composition and processing parameters on physical behaviour of high dry matter (DM) IMF systems with a view to designing more sustainable manufacturing processes. The study showed that commercial IMF, with similar compositions, manufactured by different processes, had markedly different physical properties in dehydrated or reconstituted state. Commercial products made with hydrolysed protein were more heat stable compared to products made with intact protein, however, emulsion quality was compromised. Heat-induced denaturation of whey proteins resulted in increased viscosity of wet-mixes, an effect that was dependant on both whey concentration and interactions with lactose and caseins. Expanding on fundamental laboratory studies, a novel high velocity steam injection process was developed whereby high DM (60%) wet-mixes with lower denaturation/viscosity compared to conventional processes could be achieved; powders produced using this process were of similar quality to those manufactured conventionally. Hydrolysed proteins were also shown to be an effective way of reducing viscosity in heat-treated high DM wet-mixes. In particular, using a whey protein concentrate whereby β-Lactoglobulin was selectively hydrolysed, i.e., α-Lactalbumin remained intact, reduced viscosity of wet-mixes during processing while still providing good emulsification. The thesis provides new insights into interactions between nutrients and/or processing which influence physical stability of IMF both in concentrated liquid and powdered form. The outcomes of the work have applications in such areas as; increasing the DM content of spray drier feeds in order to save energy, and, controlling final powder quality.

The primary cellular immune responses to B. pertussis antigens in infants

info:eu-repo/semantics/nonPublished